The guy smartly batted it down instead of catching it. It is a turnover.
One of the best fake punts I ever saw, the punter just sort of "got small" while the O-line "stood up to obscure the view"
The punter sort of bent over and chucked up a hail mary style pass.
One of the "punt defenders" just ran down to the returner who was signaling fair catch and got in front of him and caught the ball, and ran into the end zone with the returner just standing there going "WTF that's interfering with a fair catch" Other possible outcomes would be the returner hitting the "defender" and thus pass interference, or someone trying to block the punt hitting the punter for roughing the passer.