i would just request a refund at prefunds.aa.com self-service, reference the waiver, and see what happens.
it takes less than a week for a response, and they are ridiculously easy in processing refund requests (like, they approved a refund to OFOP for an immaterial schedule change of 20 minutes recently).
if denied, the battle is getting to use the credit when ready to book a new ticket - at which point you can take a fresh stab at explaining the waiver.
also, and only after prefunds.aa.com denial, tweet to AA with screenshot of waiver and ask just that they notate the eticket for change-fee-free use of the funds.