Mattais and Daniel was actually not robbed, they bought a collection from one of the organizers of the Danish convention, a guy named Per. As far as I know they did not have room in the car for the stuff, so per took it to his garage, and they should pick it up later. It was then stolen from the garage along with most of Per's own collection. The thief was a Danish collector of Greek heritage and he is somehow related to Hells Angels. He has known Per since the late 1990's, where he attended conventions held by Per, he was a teenager back then and we used to call him the rat, due to his rodent-like face, well that name suits him quite well now.
The German, who was robbed is a seller named Sebastian, and it was not his collection, but his stuff for sale and cash, that was stolen. I doubt