He repeated the story in front of a group of people. How surprising it was, when a stranger(R. Chaim Kurtz) in the crowd stood up and said that this story happened to none other but his own father R. Mendel Kurtz A”H .
I contacted R. Chaim Kurtz from Union City N.Y. (son) to check the accuracy of the story.
He had one correction. Reb Mendel the Holocaust survivor told R. Itzikel zt”l this Pshat he had heard in concentration camp from the Viyapoler Rav zt”l. (it wasn’t his own Pshat as I originally wrote)
Reb Chaim also added that this happened on Shabbos Parshas Beshalach (Shira) and R Itzikel was very upset hearing this sad story on Shabbos.