Momo wouldn't really need to be a adult to kill a fodder like Orochi. Hiyori will take this part. Momo will follow Luffy to fight Kaido. Does he most like kill him? Idk really know but you can be sure Momotaro battle is going happen like it or not
@sanjikun , Marco is joining the rooftop battle, prepare for another L for Marco downplayer.
However as Luffy fan I would be kinda bit worried too not just Zoro fans, because Momotaro in the end get all shine not the "Monkey". In case Momo actually really could finish off Kaido and not Luffy.