How is it you base this assumption. Is it possible in your opinion that Jehovah uses other groups as well? If not why not? If the FDS has taught doctrine that later turned out to be wrong and even DFed those who disagreed with those doctrines that later turned out to be wrong what would this make them guilty of?? Running ahead of Jehovah maybe? Being presumpteous?
Assuming to know the will or mind of God and claiming to be "directed by God" and then being wrong is not something to be taken lightly.
Those claiming to be the FDS assume they have the right to destroy lives, families and friendships on "their" interpretataion of scripture which changes at will is not being humble at all in IMO.
What is your definition of "spirit directed" and how does it differ from "being inspired"?
Would God use an "uninspired prophet" to declare his destruction/annihilation of all those who do not listen to this "uninspired prophet" and believe/teach everything they teach as present truth?
I would really like to hear your answer to these questions as they are questions have/am searching for myself.