Mariwen enjoys telling people when they are wrong.
I wouldn’t say they have permission to use bone dolls specifically, but they are prepared to argue about it if needed. You would think Blair would be jealous that Horace entrusted the doll to his niece and nephew, but he wasnt all that sad to see Phinny go.
If anyone one is curious that little trinket Mariwen is holding functions like an ID card- Merrick has one too (as do most Fauni of any kind of importance or trade). If your traveling around or need special access to certain parts of the city its very helpful.