True. If he does turn out to be Peter Pan, then he adopted a new name for himself, something not quite as unique as Baelfire, so Hook wouldn’t have been able to identify him by that. Unless someone else in Neverland knew his real name and let it slip.
Sentiments like this one make me really excited to see what happens when Hook swaggers back into SB. Neal has seen him but he hasn’t seen Neal. I know he’s all grown up now, but that doesn’t mean Hook won’t recognize him.
If someone did let it slip, my money is on Tink. She betrays Pan in the Disney movie (haven’t actually read the books, sorry!) to Hook because of her jealousy over Wendy. Instead of telling Hook Peter’s location (as in the movie) she could reveal his true identity, then the question is what is Hook’s reaction. Milah did love Bae, and Hook isn’t so much a scoundrel as he wants us to believe. I think he’d care for Bae.