Yeah, that's a bit more meddlesome than I think a parent has power over a grown child. I understand maybe expressing some concern to you quietly, but not in the sense of "we need to stop this". Unless he knew she was toxic, it's just... not a parent's business. (Which obviously you agree about). It would be different if she was still married and -together-, but if the divorce is in progress... meh.
This is from the orajel website... haven't done any research of my own though: http://pinterest.com/pin/176203404141395913/