Looking back at the photos on the third page (compact impact?) and the reported descent rate of 7000'/min would these be consistent with a deep stall? I know nothing of the MD-82 but that T-tail layout was IIRC implicated in a few losses of similarly configured aircraft many years ago (BAC 1-11, Trident).
If so, and with no engine power to help with a recovery, the outcome was almost inevitable
OC