Tailscrape or bellyscrape?
From the photographs in post #2, the worst of the damage seems to be well forward of the back door and gets progressively less towards the tail.
Judging from such photographs of the type as I have been able to find quickly, it looks to me as though the only way to scrape that far forward without removing most of the lower part of the rear fuselage is to have the main wheels up.
Could this be a case of wheels up early, flaps in far too early?