I have 2 public list custom settings. Both can be exposed via the Custom Setting UI and Apex with the Customize Application permission. However, without that permission 1 of the Custom Settings is visible and the other is not. I've granted the View All Custom Settings Permission and specifically included both of the in the Custom Settings Definitions on a Permission Set.
I can't rely on the Customize Application permission as this is a managed package and I know for a fact some customers won't grant it.
What might I be missing? I'm scratching my head a little here as to why one is available and the other isn't even though the definition for the two is both Public List.