here is no way for mIRC to know when a person "attempt"ed to mass ban. The only way mIRC will know that something happened is if that something does happen.
Potentially no, but you can get scripts to mass ban. so it would be safer to protect against it jut in-case.
That is what I said - you can
get scripts to mass ban. In a remote event, you just need mIRC to know when to trigger, such as time of day, or when a certain something happens.