The logline sets up a situation for a plot, but it doesn't doesn't lay out a plot, ?what causally follows from establishing his own cult. ?(And I'm not sure what kind of a cult it is-- religious or...?)
What is the objective goal of his setting up a cult? ?To control other peoples' lives because he thinks he knows better? ?To manipulate and exploit weak-minded and gullible people?
(As a side bar, what is your objective goal ?writing the story? ?To explore the psychology of exploiting people's weaknesses and delusions?)
And who/what opposes him? ?Who/what threatens to defeat his purpose (whatever that is)?
And why is the story classified as a thriller? ?Seems more like a drama to me. It could even play out as a comedy, but a thriller?