On a slight tangent:
Does DL ever provide mileage credit on a PNR that isn't borne of cold... hard... cash?
I would expect mileage credit on a eCert or eCredit that came from a cash fare that was not flown for whatever reason...
I would NOT expect mileage credit for Pay With Miles, Award Tickets, or eCert/Credit for same.
I read the OP and saw that the only expediture was "It turned out that I was only charged taxes"... My reaction was essentially, "Pay nothing. Get nothing."
Am I missing something?