If I remember correctly, he wasn't even a classmate, per se. Just someone who contributed something for local service. So for him, she was "Patient X who asked for an anime character figure," whereas for her, he was "The totally awesome kid who granted my special request for an anime character figure."
I hadn't thought about it from the time, but yeah, if her style changed this much, and he's already
bad with names, then of course he wouldn't remember or connect her with her past self.