Auto-delete meeting request acceptances

I'd like to create a rule that automatically deletes meeting request
acceptances (or tentatives) except where the author has written some text in
the notes/comments section (ie I accept your meeting, but I'll be 10 minutes
late).

I've set up a rule that auto-deletes anything with Accepted/Tentative in the
Subject line but what has me stumped is how to create a specific word
wildcard for the notes/comments section.

Thx