These were taken with the Z6, 24-70mm f2.8 S, and SB-910. Fabulous lens. For this venue the SB-910 was not strong enough, I should have used the Godox 360 for power, but it was in Erie PA and I did not want to fly with heavy equipment.
Your flash was powerful enough for the images that you posted here. In fact, it was too bright on the bride and groom in the last picture. Their flesh tones appear to be burned out on the cheeks. I would've dialed the flash back a bunch because to me--and this is just my opinion---I would rather be slightly underexposed on flash portraits. I can increase exposure, but once you've lost the cheeks and forehead, there's not much you can do.
If you want a more powerful flash than the SB-910, look for a used SB-800. I have 2 of them and they are the most powerful flashes that Nikon made (I believe more output than the SB-5000 is).