Yeah, wobble, doesn't sound good. Sorry about that!
I'll take Faith over Higher Education any day.
Since he's already reached that "mature" age with that mindset, it might take him reaching his senior years and bad health (or some other hardship) to make a swing around (not that I wish for it, but my point is people throw God away when they figure they can do it all themselves, until something happens to show them they can't control everything).
All I know is the Word of God really is "alive" and really can "exert power," but if a person has a closed heart (worse than a closed mind), I don't know what will turn them around. God knows, so maybe send some prayers to that effect in His direction?
Hopefully your son knows the WT and its interpretation of things is not the sole sum of what God and the Bible is all about. There's some awesome truths to be learned from the Good Book that most JWs/or exJWs as a rule have yet to even discover.
Is your son already married? Ha, just had the thought that if he met a "real" Christian lady who he admired or liked, there's always a possibility she could soften him up.