My Isle Abeens has had the same three wild Pokémon for more than a week now, despite me refusing to let them join multiple times. How do I turn them away so that other Pokémon may join?
The only way to turn away a Pokémon is to never tap them when they're visiting Isle Abeens and they still have a question mark over their head. If you've already tapped the Pokémon while it was visiting, it will not leave on its own and will have to be recruited and then released. This is not a problem since tapping a Pokémon doesn't provide any additional information.