Seems a little foolhardy though, to antagonize her even just a little bit by denying her a book room. Maybe a compromise would be better? Like only an equal book room to Ferdinand's, or a book room that's only half full.

Probably not? Like in the Starbinding, Anastasius might be expecting something weird to happen again and tell the rest of them to expect the same. Even if they don't know what that is, I assume they'll be prepared to act like they know and spin it their way.