Perhaps Peter Pan wants the saviour but he thinks Henry is the saviour. Peter Pan seems very anti-girl and since visions of the future are not the most clear of things, Peter Pan may have misinterpreted his vision to think Henry is the one he needs when he really needs Emma.
I like this!
ETA that, actually, thinking about it some more, PP could even know that it’s Emma he needs, and it’s just that he wants Henry is the bait. Felix told Bae he was lucky, he’d get to live. Well, what better way to get Emma to walk right into a trap than to rig it so that she has to come to save the life of her child who’s about to be killed.