MC is just that - MARRIAGE COUNSELING. FC - family counseling is what she is looking for. Big difference. As Thinker (or maybe it was another poster - sorry) said, co-parenting training needs to take place after the mediation and child sharing is set up, not before. There is too much hostility involved in D to try to mesh co-parenting in at the same time.
I would add that, "yeah, we might need it as well so that you and my new wife can get along down the road."
While no doubt true, don't think that pushes us in a better place. But you never know what may come up in discussion.