I have never been a runner of an instance so I don't know if there is a web interface for it that can set the admin. If there isn't then @louis will need to edit the database and set you as the admin. I don't know though. I assumed admins could be set (hence the "AdminS", notice the "S").

I don't know if a remote user can become an admin. @louis could become one if he wants.

@bob @deavmi Yes, remote users can be promoted to #groupadmin by the hosting instance's #dentmaster / admin. However, remote group admins cannot promote / demote or block / remove group members.