A very strange situation. It is quite plausible that a Russian stole art from defeated Germany. Russia has the horrible record of keeping art confiscated from murdered jews and museums and private collections of German conquered territories. They have the twisted notion that they deserve things stolen from other people. But, of course, they occupy the Crimea and are licking their lips at other people’s homes.
At any rate, It would be informative to know what is in this collection.