I'd like to suggest that the following be made to work:
anyword.*20.username @ spamgourmet.com
anyword.20*.username @ spamgourmet.com
anyword.domain20.username @ spamgourmet.com
anyword.20domain.username @ spamgourmet.com
This would allow me to automatically permit a number of messages beyond the exclusive sender, just in case the first responder's domain doesn't match subsequent responders.
Thanks again for the continued great service!