Basically if possible I would strongly advise anyone planning on running a server to use a dedicated linux host, and then install the minqlx server mod.
Then only give yourself admin rights via the normal in-built QL system.
If you want anyone else to help out with the server, only give them rights on the minqlx bot, not admin/mod by the game.
That way you always know exactly who set a ban as minqlx records it, and the reason field has to be filled in too I think, but either way you can insist that a valid reason is given and anyone filling in nonsense reasons or failing to explain properly will lose their access.