Who knows it might be true. I'm reserving judgement.
The idea that a Polish immigrant might be attracted to JWs, but later discover their darker side on YouTube in her own language, and leave, seems the most plausible and compelling part of the story to me.
What is a bit more difficult to understand is the part where, having discovered that JWs are controlling and abusive through watching the YouTube video, why did it come as a surprise to the Polish woman that she would have problems with her JW employees when she left? You'd think someone in that position would ask a few questions and try to discover the lay of the land. Not simply turn up at work to find a ghost ship. Very dramatic scene, but difficult to comprehend in practice.