I don't experience the problem you're describing, at least not on the current version of mIRC, 7.52

The On Invite event works whether or not it contains a colon before the channel name, and the default text is haltdef'able.

Also, mIRC never displays INVITE messages that are targeted to some nick that isn't you. The target nickname is different in your two examples (one ends in 'z').

Experiment.

Code:
On ^*:INVITE:#: {
  echo -s INVITED: $nick , $target , $chan
  haltdef
}


Code:
/parseline -itqp :pballz!pball@pball.tigre.lives.forever INVITE pball :#chan

/parseline -itqp :ChanServ!service@rizon.net INVITE pballz #chan

//parseline -itqp :ChanServ!service@rizon.net INVITE $me #chan


You may have a custom theme script that makes On Invite messages pretty, and you forgot to turn it off.

Well. At least I won lunch.
Good philosophy, see good in bad, I like!