By virtue of their valid baptism, and their belief in Christs divinity and in the doctrine of the Trinity, Seventh-Day Adventists are both ontologically and theologically Christians. But Christians, once separated from the Church our Lord founded, are susceptible to being “tossed to and fro and carried about with every wind of doctrine” (Eph. 4:14).
There is such a thing as a “Christian Cult”
You may disagree.
That is fine.
Quoting the Catholic church to make a point about another church is some real funny $hit there sparky.