By xmas, 1942, most of the German Jews were ash. PIUS himself spoke up with the Official Voice in xmas 1942--with the Allies upcoming victory plain to see. And this is your evidence--a pastoral letter that's too little, too late? BFD.
Too late for what? I think the war dragged on for a few more years. BTW, have you come up with any creditable sources for your fantasies yet?