This speculation could easily turn into a witch hunt. Wait until we have something more concrete to go on before you set up that duck scale.
Agreed. If it wasn’t Wario, though, or someone similar who delights in ban evading, such as a current non-banned member, they might not have covered their tracks at all.
This is all assuming that you guys check IPs and ban IPs and such. Don’t think I’ve seen that confirmed, but I don’t doubt you have that bare minimum of functionality.