The term gamemaster is/was a very transparent attempt, from a certain small group (none of whom I am addressing), at pushing a narrative of "new management" (which is an incredibly arrogant term in itself) and distancing our new "staff" (again, arrogant) and mighty overlords from the admins they took the server from, to make us all believe how great and awesome they were going to make Discovery.
It's an awful, horrible word, and the colour is just plain wrong.
I think you should rename the role back to Server Administrator and change the colour back to its old green.