My reasons for informing your in-laws of the WAW's EA's was not to get him to talk to her but to let him know the truth about what's going. If the family & friends begin putting pressure on the WAS, they shut everyone out. That is why they often get a new crowd to run with. I believe that parents have a right to know the truth and should hear it from either the LBS or the WAS other than somebody else. The WAS will mold it to sound biased so it is better for the LBS to tell.
You cannot control what your FIL does and if he talks to her, then that is his business. She will probably break ties with him to some extent.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!
