I still don’t buy it to be dambuster.

ED927 AJ-E came down near Möhnetalsperre

I alway thought AJ-E to have crashed near Rees. Rees is situated near Bocholt. And Bocholt is about 120 kilometers away from the Möhnesee. (And wasn’t it even supposed to bomb the Sorme dam anyway?)
By the way, according to ebay the seller seems to live at 51588 Nümbrecht, about 40km east of Cologne (80km to the Möhnesee, 100km to Haldern – as the crow flies of course). No wonder, why he has to dig at night. 😉

It might be wreckage of a Lanc all right, but there are doubtless still many small remains in German soil. Even at the supoosedly cleard sites.
In my opionion they just claim it to be da dambuster to get more revenue from it.