I am not going to comment on whether it is ethical or not,that is his buisness and not mine.
BUT,the video is definately edited(which most are).He is in no way pulling back to take a 100 yard shot.You aim higher than he is when shooting that far,I have done it many times.Even at 350 fps.
So it is evident to me it is just a promotional stunt and he may never have even come close to taking a 100 yard shot,which the deer doesn't look that far to me but who knows with video equipment.
My last point or question really.Am I the only one who thinks he made a bad shot? Usually when a deer kicks up in the back,like this one did,they were gut shot.It might be because it was slightly angled away and he had to shoot back to make it but it sure looked like a gut shot to me.