One thing that seems very much like future-seeing, and not just knowing how a magic arrow works or predicting human behavior, is knowing Emma would come to Storybrooke on her 28th birthday. Even if he planted the book and maybe somehow subtly suggested to MM that she give it to Henry, and even if he was observing Henry and knew he was piecing together that nobody else in town was getting any older or changing—predicting that Henry would make his way to Boston and find Emma on her 28th birthday and that they would return to SB on that very same day, was an awfully accurate stab in the dark. I agree that Rumple does not see everything about the future, but this one is hard to explain away.
Do we know how Henry got his bus ticket to Boston? I just went back for a quick look of the scene where Emma gets into his email and they find out he’s been on the mommy finding website and that he stole Mary’s cc, but I didn’t see anything about a bus ticket there. Perhaps Mr Gold bought the ticket and got it to him somehow without Henry knowing. The kid was starting to put stuff together from reading the book and he’d found his birth mother’s info online, and then this bus ticket dated on her birthday magically turns up. Of course he’s gonna go catch that bus, and chances are Emma’s gonna bring him back home immediately.
Of course, if it turns out they did address Henry buying the bus ticket himself at some point, we’ll just disregard this post. LOL