Go for it. I have no loyalty to those people. They did not claim to be prophets of God, and even if they did, who would believe those racist pigs?
Now I do believe that you have some loyalty to Brigham Young, don't you? Will you renounce him as a prophet if it can be proven that he was a racist?
Will you renounce Paul for being a sexist? Will you renounce Peter for being racist, even after he was commanded to take the Gospel to all people, he still didn’t for a long time.
Again, men are men, and prophets are human. When you come to understand that, you will know that the Lord works through men, despite their frailties.
Only one was perfect. And it wasn’t you.