The staff will offer players who fit their criteria, not off the rankings of other services. It really is not odd at all. The kid would be unknown to the internet if his video was just out there as it was not super impressive. But once the rankings list comes out, suddenly there is this increased perception of him as a player.
Frankly, I'm not sure where his position is on the defense live, in Ohio State's scheme at least. He isn't explosive enough to play the 5 tech and be an outside guy. His competition is poor so it's hard to get a read on his toughness, i.e. he's bigger, stronger, and faster than everyone he plays. How does he respond to guys he isn't physically better than?
Does he have enough "dirt" in him to play the nose tackle position? In my opinion, that is the best fit for him if he can do it. If not, he will probably be more of a 2/3 tech guy. And there are probably better athletes out there for that spot.