Why is Magneto willing to tolerate Mr. Sinister's presence, considering that Sinister was a Nazi?

As we all know, Magneto is a Jew who survived Holocaust and he has a well-known grudge against Red Skull because he is a Nazi (he even tried to bury him alive once). Yet, when he was on Krakoa, he never tried to attack Mr. Sinister or at least question his presence, considering that Sinister was also a Nazi who used to work with Mengele during World War II. Why?

Yeah, I know that Magneto's biggest flaw is that he is a hypocrite, but how exactly can he justify allowing Sinister to wander around Krakora, considering that Sinister was once a part of organisation which tried to kill him because of his ethnicity?