While I'm no fan of the Watchtower Society or the religion of Jehovah's Witnesses, they do not physically kidnap people and force them into service into the religion.
They may influence someone to become so engrossed in the religion that they forgo their family ties and relationships, but that decision is the decision of the individual, though somewhat indoctrinated he may be.
When you say, Friend of the JWs, you mean some other group, I've never heard of them.
If your son is missing, you need to call the police.