Have your son consult a lawyer. The transfer for the divorce should have been recorded. There's no such thing as a "fraudulent" quit claim. The quit claim only transfers whatever interest the person has without making any representations as to what that is. If she had no rights to the property, nothing was transferred. The first step would be a title search on the existing recorded deeds to determine what is in effect. Then if your son feels a correction is needed, that can be done.

