Crackpot theory that randomly crept into my head whilst watching Manhattan. Wasn’t sure which thread to post it in, because bits and pieces that it takes into consideration are being discussed all over the place right now. Anyway, this assumes that the dagger PP is typically depicted as having will be a thing in the show too, and that it will be a similar type of thing to PP as Rumple’s dagger is to him. It also assumes they are brothers, (so bear with me if you’re not on that team).
Two dagger wielding, dark magic beings.
PP wants to put an end to the dark powers.
PP and Rumple are brothers, so share blood.
As such, it must be someone with that same blood who is the key to ending their dark magic.
Bae didn’t qualify because he had no True Love mojo in his DNA and it’s gonna take magical mojo to get the job done.
Henry qualifies because he has True Love mojo from mom + Rumple and PP’s bloodline from dad.
Double WIN with his genetic makeup means Henry loses out and gets sacrificed. By being stabbed in his super duper Believer heart with both daggers.
Perhaps?