I have an FJ-issued ticket that includes an FJ-marketed codeshare on AA (SEA-LAX) and then FJ-operated flights (LAX-NAN) that was flown earlier this year. The frequent flyer number on the ticket was for AS (our primary program), however after the fact, mileage credit has been denied for the FJ-marketed codeshare on AA as only FJ-operated flights can earn according to the AS award chart (LAX-NAN posted to AS as expected). I've submitted an online request for this flight to be credited to AA instead, but it seems to have disappeared into the ether. When calling AA Customer Service to inquire further, I was told that frequent flyer programs could not be changed at the segment level and can only be done for the whole ticket, and that since the AS number was in the ticket there is nothing they can do, despite having documentation from AS that they would/did not credit the AA-operated flight so it's not trying to double-dip.

Is there any way to get this segment credited to AA retroactively or am I SOL?