They are absolutely right. Mormonism is no more Christian than is Islam. Both of them were flaky neo-pagan cults that referenced a few Biblical things (mostly OT, but some references to Jesus as a prophet) and then went off on their own...the planet Kolub, the founder looking through a crystal in his hat to find gold, the married god with his harem, male believers getting their own planets, the prophet getting child brides, killers getting 72 virgins, the black meteor in Mecca with its vagina-shaped silver hole...it’s a little hard to tell the difference.
The Catholic Church does not accept Mormon baptisms as legitimate, incidentally, because the Mormon intention is not to baptize a child into the life of the Trinity, but to claim the child for their cult. I think most orthodox Protestants don’t accept it either.
Thanks for the comment.
You hit it right about the RC Church NOT accepting the Mormon baptism. What surprised me is that you use the term “Orthodox” in regards to the Protestants, unless you are refering to the Eastern Churches? I tend to use the word “conservative” in regards to churches, but that is me.