I reckon he's lucky he was getting out when he did, it seems to be getting a bit faster and less relaxed than when it first nudged him. From the movement of his camera I wouldn't say that he was "suddenly bumped violently" nor would I call it a "massive thump". And judging by how much of it he got in frame when it was right in front of him side on, I'd be surprised if it was as big as he estimated. Balls of steel though, kudos to him for keeping his cool every time it turned back toward him.
It was 2.5 metres at best, if it was three and a half it would of had the jaw strength to shred him apart, judging from its behaviour it really wished it was 3.5