Not that I’m any Putin fan, but looting took place on both sides. His response to Merkel should have been, “Sure. You return the Amber Room and we’ll return the Eberswalde Hoard.”
The Germans did way more than their share of looting during the war.
If you ever see the movie “Come and See”, you’ll realize that the Germans got off very lightly, all things considered.
The most accepted theory is that the Red Army destroyed the Amber Room inadvertently in the fires that raged in the seizure of Konigsberg.