I am glad to hear some progress is being made on the legal front.
I like that the right of first refusal issue is being resolved. Your in-laws should not be allowed to intercept the kids.
Playing this game of divorce is indeed no fun at all. However, you must remain strong and not show mercy. Keep that big legal gun cocked and loaded. Put trust in your lawyers advice, but also, dont be afraid to question what your lawyer's strategy is.
It may be the harsh reality of getting some legal beatings that may convince your STBXW that it is best to try and work together peacefully in coparenting.