The problem is with Budget, not Delta. The problem is ALWAYS with Budget, not Delta. Budget customer service is notoriously inconsistent, their boilerplate responses have made it into the Guiness Book...how you will fare (no pun intended) will depend totally on the luck of the draw as to what customer service rep will field your email inquiry. What it really comes down to, is how bad you want your miles. In my youth, I went as high as corporate headquarters to make an end around customer service to get missing miles.. 81.3% of the time, if you are aggressively persistent and somewhat annoying, you will "succeed" through budget customer service, but it will take 2 years off your life.
Yes, one has to wonder why budget has not put a softer touch on their customer service.