Mikejw: Imagine how his witness in laws feel?
I figure they feel like anyone else who has had to deal with him. He does not even seem to spare his wife and kids from his narcicissm, gaslighting and bullying. And the more anyone objects to how he treats them, the harsher he becomes.
As for stopping them from seeing their grandkids, I'm guessing that Dijana has them most of the time and she's probably not on the same page as he is about how they are cared for. What is he going to do? Demand to have them full time? I doubt he wants that, that would mean the kids would no longer be a convenient prop, they would be an actual responsibility.