Try this:
Code:
on *:text:!invite*:*:{
  if (!$1-3) { halt }
  else {
    var %passwords = password1,password2,password3
    var %matchpass = $wildtok(%passwords,$3,0,44)
    if (%matchpass == 1) {
      .msg Mrbot invite $nick $3
    }
  }
}


And yes
on *:text:!invite*:#channel:{

We don't just write the scripts, we put them to the test! (ScriptBusters)