One thing I could do is letting Modders include a Cert inside their Mod to at least validate their Identity (and maybe even “reserve” a Name or two using a regex). This would NOT grant them access to the Server, but it would be a way to communicate to the Host that whatever person is about to join did make that Mod (like to validate that they wanted to debug something).
Could also be used to limit the time of the Modder on that login to “an Hour and/or until they log out” or something.
And I really do not feel like selling Names to people, that is about as bad as N F T s, just without the whole destroying the world aspect.