I haven't run into this before but I take it to mean that the citation shall be voided if you prove that you have a monthly pass within 72 hours. So I would take in what you've got and go for it. It sounds to me it will be dismissed.
It doesn't sound like this section about proof of eligibility for discounts ywas intended to apply to you, or to the tickets themselves.
Leaving your monthly pass at home isn't addressed in this section, and I doubt it's addressed elsewhere, but I also doubt that you have anything to lose by trying to contest the citation, maybe you'll catch a break.
Disclaimer: Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.