Well considering this might be is last big BB payday. Can’t blame him for trying. Probably assumes that 200 K offer isn’t going anywhere.If he wasn't asking for at least $300K I'd be surprised.
If Iowa has offered more than $200K I'd be even more surprised.
Obviously, that topic had to have been covered before he was invited/accepted his visit.
My personal theory is that he thought by coming on campus he could negotiate an uplift on Iowa's existing offer to something closer to what he's hoping to get, and by dangling his immediate commitment right on the spot if Iowa bumped it up.