[jerod]

Somebody likely hid their stash from the NAZI’s, who then took them to the nearest death camp. Nobody leaves that much money hidden for too long. So the true owner likely died during the war.

[Drew68]

So the true owner likely died during the war.

My first thought as well.

Probably stashes like this all across Europe placed there by people who didn't make it out alive to retrieve them and told nobody about them.