Isn’t it reasonable to assume that (many? most? all?) the temple leaders, Judas, and the crowd should be included in the them of “Father, forgive them, they know not what they do”? The Romans certainly didn’t believe in Judaism, and can hardly have been expected to recognize Jesus as the Messiah and the Son of God. And Jesus never gained a very significant following among the Jews. It is difficult to imagine the Jewish leaders of the day or the majority of the Jewish people believed Jesus was the Christ and nevertheless argued for his execution.