Not to mention the single wish could be used to go home. Kinda an easy-way-out, but I'm just sayin'.

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Quick question to you two: do you think a bunch of backup motivations would do? For instance, we start with the assumption that they want to confront Galileo or want the wish. After all, he may WANT them to stay, but he's just toying with people at this point, so them leaving doesn't pose a problem when he can grab more, or even the same people. Maybe after a certain amount of refusal, he could throw in a threat to kill their loved ones or family, announcing them by name or showing them images (because he can 'see' in his own way where everyone is located), then if that doesn't light a fire under them he steps up to threat of eradicating their realm, leaving them without a home to go to, then as the final fallback for any straggling left, he can simply threaten their lives if they don't push forward as I mentioned earlier? Like, these could go in any order.

Additionally, I was considering adding a few parts to the CS (the one I'm going to have added to your original) that make you outline weaknesses he could exploit, that way it feels less like railroading if I'm targeting specific parts for each person. This is for your speculation, and the first of the few ideas I had kicking around.