That their leaders are not leaders (because only Jesus is the leader) but their leaders are merely "taking the lead."
That those leaders are directed by holy spirit, which allows for errors because they are not inspired. Yet, what does being directed by holy spirit mean?
We could also look at their teachings on blood. They follow what they claim is a literal application of the improper usage of blood when it comes to transfusion, yet those same scriptures don't prevent them from allowing modern medicine from using blood for tests instead of what they say is the only proper use of blood- sacrifice and disposal.
Then there is the whole blood/fractions thing they created.