Not sure what you mean by DDM but I think what you have there is simply machine doubling on the mintmark. Mintmarks were not punched into the working die when that coin was struck so the only ways there would be doubling on the mintmark would be if the entire obverse die was doubled (which I see no indication of) or if there is machine doubling (which appears to be the case).
After 1990 ,I believe the mint mark on Jeffersons were added to the master die, and basically eliminated the idea of a repunched mint mark. It is was referred to as a DDM, but as a repunched ( RPM). It appears more like machine doubling damage. best estimate. Tie with Hobo, but he won
