As I mentioned, there is an organization that I am a member of that deals with Parental Alienation. It is headquartered in Toronto, but is a global organization. It was started by a dad who was alienated from his children. Joseph Goldberg.
dealing with problems that relate to "Parental Alienation." I think your son should contact this organization. You can let them know that I recommended him so that they will provide him with whatever information he needs --- What steps to take to regain his parenthood. Parental alienation is a form of parental child abuse. It must be stopped. This organization will help in what steps to take.
Hope your son finds the success that Joe Goldberg did.