Sure is a heck of a hole. The question I'd ask is if there was anything in front of deer when the shot was taken? Possibly is hit something near the deer, fragmented and then made the hole.

The hole sure isn't common, but could happen. I've seen weird things like that happen before. I once shot a bobcat with a 30.06 with no exit hole. A perfect broadside shot, and I studied inside and out for a hole, but nothing. And have the tanned hide to prove it. 99.9% of the time the bullet would've wizzed right through it.