“I know of Mormons who are Christians. “
It’s an oxymoron, unless that Christian who was a Mormon was utterly ignorant about the teachings of Mormonism. Maybe a fresh convert.
There’s a lot of born-again Christians in this world who are nevertheless deceived. None of us have got it all right. And some are way off. But, “He that comes to Me I will in no way cast him out.” The blood of Jesus is effectual to cover all our sins and errors and to “save to the uttermost.”