I will also let him know that unless and until I have divorce papers in hand i will continue to fight for my marriage and if I can find a way to expose him without hurting my wife, I will, and that he should back off as long as we are still married.
Please don't tell the OM this ^^^^^^^^. He is not your friend, does not care how you feel, does not have your family or W's best interest at heart, and he is not an honorable man. Do not tell him that you plan to expose him!!!! That will defeat the purpose and tip your hand so that he can discredit you before you can make anyone believe what you say about him.
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!