I think that the provenance of these pictures was established a few years ago, and that they are now held by Time Life. Possibly some have just been newly released, but color photos of the house itself are very well known, appearing in various contemporary books, and even on sets of postcards (I have a few cards from the time, and some have the description "Agfacolor" in the printing on the reverse).

There is a lot of info about Agfacolor from its first introduction on

I recall also a few years ago that pictures from that era taken on Kodachrome were published...I recall a thread (not sure if it was here or on another forum) which queried if this were possible, and it seemed that there was a Kodak lab in Berlin up to the time the US entered WW2.

As David says, it is good that these are preserved and published to remind us of the evils of the time.