When they are in the train station in Berlin, a woman panics and begins to sing Di Partizaner Lid. First off, it's a Yiddish song, and German Jews were notorious for not speaking Yiddish; also, it was a song written/sung by the Jewish Partisans of the Vilna Ghetto, and would not have been known in Berlin until after the Shoah.
When Nina recites Shema Yisrael, she uses Sephardi pronunciation. That pronunciation was not used in Europe until sometime after Israel became a state (in 1948).