I call bogus.
A) I can't tell that he flexes any part of his hand to pull the trigger. Given his heightened (and, I'm guessing, inebriated) state, I would fully expect him to jerk the heck out of the trigger.
B) There's a fairly noticeable delay between the report of the gun and the gun beginning rearward travel. Presuming the camera was fifteen or twenty feet away, the sound and onset of recoil should be nigh instantaneous. It's especially evident in the slo-mo replay.
C) Watch the barrel of the gun as it comes back. The bore axis was above the shooters wrists (the point of rotation for his particular "grip"). The gun should have rotated up under recoil. It didn't. It tipped down. That's what would happen if he was pulling the gun back, not from the gun coming back under recoil. Again, slo-mo replay shows it pretty definitively.
D) Everything seems a bit too staged, especially the camera holder's stability as the shot is fired. Even if the camera had image stabilization there should have been a noticeable flinch. Something with that much recoil that short a distance away and almost perpendicular to the camera is going to create quite a bit of noise and pressure. I can't thing of very many folks, even professional shooters, who wouldn't flinch at least a little bit. The camera stays almost rock steady, though not quite enough to be on a tripod.
Brad