Thanks for your letter. I have to say I am little embarrassed that people are saying--and writing--things like that anywhere today. Historically Jesus was put to death under Roman law ("crucified under Pontius Pilate") and according to our theology he died because of the sins of all men. The Jewish leaders who asked for his death represent the envy, lack of courage, bureaucratic inertia, etc. which is common to all of us. Those who want to put the blame on "the Jews" are those who are unwilling to face their own sinfulness.
By the way, have you read the Vatican Document We Remember: A Reflection on the Shoah? It has a lot of material you could bring to people's attention. Pope John Paul II drawing on the Second Vatican Council has made many statements on this topic since he lived thru the holocaust as a young seminarian in Poland and lost many friends, both Jewish and Catholic, to the Nazi horror. Have you been able to find some of this using different search engines? If not, let me know and I will find a few URLs for you.
Fr. Phil Bloom
Pope Pius XII and the Shoah (New Yorks Times vs. New York Times)
Was Pius XII Hitler's Pope? (letter published in Brill's Content)