The story is interesting, but even though it has a diverse ensemble cast, I think it would be better to frame the struggle around one central character as the protagonist. ?And to identify where the story takes place. ?So either, something like:

The true story of how a pacifist [French, Polish, Italian or???] priest risked his life to save 5,000 Jews from the Nazi death camps by rallying the support of a violent resistance group, an amateur forger and a one-legged female spy.

Or better:
The true story of how a one-legged female spy helped to ?save 5,000 Jews from Nazi death camps.

Better because the one-legged spy ?is by far the strongest hook. ?You could but I don’t think you would have to name her nationality because more important is the fact that she was one-legged. ??And the logline is short and to the point. ?

Dare I say it fulfills the definition of a ‘ high concept’ story: 1] A unique character 2] whose objective goal can be stated in fewer than 20 words, and in the age of the internet 3] it can be stated as a tweet with characters to spare. ?A three-fer.?

And that is why the concept gets my vote.