I dont think ive ever heard a final answer to this question actually.
Morally, when it comes to WWII photos, I think that if a person holds a period printed photo from the original negative in there possesion, they should have the right to publish or whatever esle. In one way or another, the original owner/photgrapher has obviously passed on the photo at some point......therefore ending ownership IMO.
But as stated, who knows how many copies were period printed from the original negative, and what the law is in this case?
Interesting conversation topic....but Im afraid we will never get a straight answer! If so, that would be good.