The only downside I can see for your insistence on staying with the ancient version of PS and LR is that when you finally, if ever, cave in and get the newer versions of the software you:
A. Won't recognize them because over the intervening years so many improvements and capabilities have been added to the programs they will seem like a foreign language.
B. You will be severely injured by kicking yourself when you find all the incredible post processing capabilities that have been added that make creating works of art out of simple snapshots extremity easy.
C. That those of us that have assimilated the changes over time generally haven't suffered "sticker shock" from the evolutionary pace of the changes.

I shoot with my Canon 100-400. You'll definitely need both ends of that range. I take along a 1.4x teleconverter for really long reach but only if the safari vehicle is going ot be stationary for longtime for a far off shot.
Be forewarned though the animals are often pretty adapted to the safari vehicle and even 100 is too long for a shot with a subject at 10 - 20 feet. So you'll be fumbling for a 24-105 or similar.

Seriously
If you felt you needed a new computer because your old model was getting a little week in the knees, why not spend $10 per month and get the subscription to PS and LR along with all future upgrades?
The latest LRCC which is not cloud based is vastly superior to the older versions in terms of almost any post processing you may choose to undertake.
Trying to live in the past by sticking with outdated and unsupported software is simply an exercise in self flagellation. Get over the mental dislike of the subscription model of software ownership and move up tp a vastly superior product which will quickly have you doing post processing acts you never even thought of.
No- I don't have any vested interest in Adobe but do hope you will advance yourself to much more fun in post processing.

I would second most of the above except shutter speed.First go with auto Iso and don't be too tight on the upper limit. Topaz Denoise will clean up any problems if you get too high. Next let auto Iso allow you to go up to f18 or so for maximum depth of field and keep your shutter at a minimum of 1/1500 th. Reasons here are compound. First, unless you are on a private tour there will be multiple people in your vehicle. And nobody ever sits still. So your platform is not stable even if you could hand hold reliably at 600mm. Second, the idea of having some sort of pad or bean bag is a bit optimistic as rationale for stabilizing the camera. Fine if you're sitting for long period with your target shot not moving around much. Reality is the environment will often be very dynamic and some of your best opportunities may appear somewhere that you can't swivel to. A lot of your shots may involve panning and you won't have time to stop and change the shooting mode. You really need 1/2000 or 1/2500 for birds in flight or a running cheetah.
In short you need to have your camera set for the unexpected. Many of the best opportunities only last for a few seconds and will be a past memory if you're fiddling around with settings.

Save it as a PDF or if you want music accompany as a video.

I agree -mostly- with murphle. Most of the image seems blurred. I could fake it a little and argue that the beak back to the white ruff around the neck may be relatively sharp. So from that I'd argue against camera shake.
I find that there are a number of issues that come in to play. Assuming you were using a high speed multishot setting you should look at (if you can) where your focus point actually was for the shot you selected. Sometimes in tracking the bird you can get the focus point off on some branches somewhere. The camera often doesn't care where you focused just that it had something nearby in focus.
My solution is somewhat consistent with what others have suggested
1- get the shutter up to at least 1/1600 or better although in the instance it appears that eagle was gliding so wing movement would not be a problem.
2- get more depth of field. How close were you to the bird? If the camera gets confused with a part of a branch nearby, more depth of field will sometimes compensate.
3- Open up your auto iso range and fall back on Topaz Denoise This will allow the higher f stop and shutter speed with little or no penalty.

I've practiced quite bit with my 5D IV setting for shooting BIFs at Half Moon bay in CA. Generally there, background objects don't come into play. But if, for example, you're targeting one pelican in a group and trying to track one bird, even at 560 mm, it's hard to keep the focus point on the desired target because the image is often pretty small. The introduction of tree branches jsut further complicated the problem. Too many extraneous target for auto focus.

Don't know where you're you're located.
Try Click-Away They are in the SF Bay Area but may have other locations they serve

A side note on HEIC files. Apparently Adobe LRcc doesn't appreciate these files. To show its distaste it locks up. But once that is the file that you closed on when using the "Close app" function in Windows 10 that is the file LRcc will try to open with when you restart the LRcc APP.
Kind of messy to undo the problem. First rename the HEIC polluted catalog to some temp name.Then had to create a new Catalog giving it the name of the catalog that had the HEIC files but with only one folder with no HEIC files. Then could restart LRcc. Then cleanse the renamed catalog of HEIC polluted files. Then unrenmae everything so that I can get back into the catalog that has almost 4T of edited photos. Now that LRcc reopens and it can't find the polluted folders you can go back to remove those folders that had HEIC files that LRcc may look for.
Needless to say I won't EVER try to bring a photo folder from my iphone into LRcc again. I only did it so I could edit the file size down to something that I could e-mail. Sadly there are a number of other iphone functions that when ones tries to integrate into a cross platform activity things come crashing to a halt.

I agree that M +Auto Iso is preferable in most situations. I would add in Topaz Denoise AI. I took some pics of an Owl at a Wildlife Rehab benefit dinner. The light was VERY low to the point that I really couldn't see the bird really well. The attached was with a Canon R5 16-35 mm f3.2 1/250th The auto Iso went up to 25600. The unzoomed pic actually looked pretty clean but when zoomed 4x and the exposure level was brought up on LRC there was a lot of noise. Topaz wiped the noise clean.

For what its worth you say you've searched for .lcat files. Lightroom (at least mine) uses the extension *.lrcat. That "r" could make all the difference. Also, LR will automatically ask you to allow an update of an old catalog to make it compatible with the features of a new release. If you don't allow the update it will make a new catalog and stuff the old catalog(s) who knows where. But it's probably somewhere where you have the user files for the LR APP.

Go as far north as you can - like up to Montpelier and then work your way south. My best luck has been the first week of October. But remember once the leaves begin to turn one rain storm or light snow and everything is gone.

I've been successful with both Android and iPhone 11 using a USB C to USB A cable to directly connect the phone to my Windows computer. It comes up as a storage device. Then navigate using windows explorer to the DCIM folder and the photos file and download directory to the computer. Then go into Light-room. I've found Lightroom to be a bit picky in what sources it will recognize e.g. can't download to Lightroom from my NAS.
When I experienced some problems originally I got led down a rabbit hole by Apple Support into trying iCloud for windows. Took a lot of incompetent help from the Genius Bar folks who really had never touched a Windows product to get nowhere in trying to make it work. Finally on my own hit upon a series of convoluted steps that got a file down but I don't think I could repeat or even care to try.
Also got mixed up in the download with pics I had taken using the Photo option with pics taken using Live which created a bunch of short .MOV files. I didn't know I'd been using Live - my big fingers were careless. Your problem trying to do a direct download to LR may have been the Live files that I think use a movie format not supported by Lightroom which could have caused it to stall. Live creates both a .jpg and a .mov file and when I did get the download from the DCIM file I had to select out the .jpg from the .mov before Lightroom would upload them.
Needless to say in going through this torture I seriously considered using a hammer to free the files from the iPhone and scooping them up with a shovel into my computer.

WOW! or is it wow?
Have we run out of trivia to argue about? How about opening the argument further to include Raw, rAw, raW, rAW , RAw, in all of the possible fonts and put upper and lower limits on font size.
Give it a break!!!!

The best I can offer is go before Easter and after labor day and get into the park before 7AM for anything on the canyon floor and plan to be out before 10AM.Come back after 5 PM. Between 10 and 5 drive over Tioga pass and see some of the high country or go as far as Mono lake. Don't figure to get anything like a meaningful waterfall pic this year. If not dry they'll be just a trickle. If you have options go on a rainy day.

From MHO all of the delivery services have become rather flakey. This includes UPS, FedX, Amazon Prime, and USPS.There are, quite literally, 11 different widely dispersed places around my property that the various drivers leave packages. So any time I'm expecting something I get the added thrill of an Easter Egg Hunt.
All in all UPS is the best for me as long as the package happens to be being delivered by my regular driver. He knows where to deliver packages and, if its wine to keep it out of the sun. And he will "sign" for me when a signature is required. Others ???? anything goes even if its raining sometimes packages are left where they get wet sometimes packages, even little things in cardboard packages tossed over the gate in the middle of the drive - quite invisible at nighttime. And soaked when its raining - our drought in CA makes that a lower risk now.
One thing to note - don't pay for overnight delivery on Thursday or Friday orders. If the package goes out late on Thursday or anytime Friday you'll not see anything until Monday at best.