How so?
Mormons believe in Jesus as their Lord and Savior same as most Christians (believers).
Pretty much all denominations are similar in teachings.
The only issue I've seen is the Lack of knowledge from Leaders.
I have no idea why Albion brought up Mormons. But since he did I can see reasons for Christianity Haven excluding Mormons from "Christian theology", for example, because Mormons reject several of the doctrines taught in the Nicene Creed; specifically,
The Church of Jesus Christ of Latter Day Saints rejects monotheism, the Holy Trinity, Christian teaching about the incarnation of the Lord Jesus Christ, and the
one, holy, catholic, and apostolic Church. And since these things are the heart and core of the Nicene Creed it can be said with a very high degree of accuracy that "Mormons reject the Nicene Creed".