This may be an interesting one for the Travel Troubleshooter..
Christopher Elliott is the ombudsman for National Geographic Traveler magazine. E-mail him at [email protected].
He's featured on cnn.com... seems like this could be a situation where an ombudsman could help. Delta can be tough to deal with under normal circumstances.. this looks like it will take many man hours to get to the bottom of.

I'd have a difficult time even bringing up bank records from 2000 to show paid fares... this seems pretty ridiculous to me.