There are two things going on here...

One is that many large venues use fluorescent or sodium vapor lighting. That "fools" camera meters. Basically the lighting cycles on and off very rapidly. 60X per second in the US (50X a sec in some other parts of the world). This causes a lot underexposure problems when shooting under that type of lighting. Typically there's a yellowish color shift related to the under-exposure, too.

Your Canon 80D has an Anti-Flicker mode that can solve the problem. When that's enabled the camera will detect the light cycling and time the shutter release to match the lights' peak output. Except for the most entry-level models (Rebel T7, SL3 and T100... M50 Mark II and M200), this feature is found on all Canon DSLRs and mirrorless since it was first introduced with the 7D Mark II in 2014.

Shooting sports with faster shutters speeds "under the lights" I had a lot of trouble with lighting. Prior to the 7DII there was no real solution. Flash wasn't an option and shutter speeds that can reduce the problem are too slow for sports (also make hand held shots less stable). About half my images under the lights would have exposure problems, often to the point the images weren't recoverable. All I could do was take lots of extra shots to increase the odds of getting some good exposures. Once I got cameras with Anti-Flicker and started using it, I see very, very few images with those problems any more. It's been a huge game changer!

You also will get better results if you set a Custom White Balance. Yes, you can try selecting the Tungsten WB preset, but it will be wrong as much or more often than it's right. You also can shoot RAW and change from one WB preset to another during post-processing, but that has the same problem. Lighting comes in a wide variety of "colors". They also change color rendition as they age. Unless you install the bulbs yourself or buy a very expensive type of color meter that can tell you the temperature of the lighting, it's just a guess what you're working with. And all the preset WB are essentially just estimates. Rounded off numbers, rather than precisely matched to the actual color of the light.

Learn to set a Custom WB and you can eliminate these sorts of problems. It's easy. All you need is a neutral target. I frequently use a couple Lastolite (or Manfrotto) EZ Balance for that purpose. These are a nice, large fabric target that folds up small for storage. EZYbalance are available in three sizes. Mine are the medium size (20"). https://www.bhphotovideo.com/c/product/375202-REG/Lastolite_LL_LR2050_EZYBalance_Grey_White_Card.html?sts=pi&pim=Y

For portraiture in particular, I sometimes instead use Warm Card targets. Three of those are designed to create a slightly warmer image that's often desirable when shooting portraits. Warm Cards also come with a couple that will cause a cooler bias, as well as one to help correct the ugly greenish tint many fluorescent lights cause. There's a gray card/white card that's perfectly neutral, too (serving much the same purpose as the Lastolite targets). Warm Cards are available in two sizes. I use the smaller ones. https://www.vortexmediastore.com/pages/warmcards-white-balance-system

EDIT: The EXIF says no flash was used.

Finally, I hope you don't mind... I looked at your image in Photoshop and did some tweaking. I added a #80 cooling filter as well as just a little green. It started to look a bit flat, so I boosted saturation a bit and ended up adding a weak red filter. I also adjusted the mid-tone exposure slightly. And, sorry, I had to try to straighten it a bit! But you can only do a limited amount of corrections working with a JPEG such as this. See below for the results (be sure to click through to the larger version, for some reason the "thumbnails" in posts here on UHH often look oversaturated and color shifted):

Please don't let the bores get under your skin. Ignore them. There are plenty of kind people here who are willing to help.

Here is a "glass half full" thought:
Could be Les didn't know how to fix it, so that's the best he could offer.

And sometimes "shoot it again" is the best answer. When stalking a landscape photo for example, you can go back and shoot it again, try different lighting, different weathers, different time of day. However it was not the right answer in this case.