Fumble on the return out of half time would have been the game changer.
I agree with those who said the runner was likely down. BUT, I also agree that the video didn’t seem to show anything to overturn. You can see the runner go down, but can’t see if the ball is possessed or loose. My understanding is if you don’t have indisputable evidence you can’t overturn.
likely the right call, but sets a bad precedent for a very gray area to the rule.