I do think it's important to keep in mind that he is already aware of the availability of AA and counseling.
Reminding him of options and telling him what to do (not that you're doing that!) are two different things.
It doesn't seem like you're putting yourself in the middle of things unless you start to invest some sort of emotion in his decision to seek outside help.
It's too bad that his dad sucks - you'd think he'd want to do better for his own sons.
-TC