Soooo I've had this key for a few months from one of the Fanatical bundles. Since it won't allow Germans to claim and I could never be arsed to sit down and figure out VPN and stuff... There you go, one of you guys gets it.
I don't know if there's any region restrictions other than DE/Germany, so I didn't set any restrictions. And maybe some Germans are VPN-savvier than I, so might as well let them enter? Either way, let me repeat, for the vanilla German steam user, this key will not work.