My thought is that if these people beat up your son and harm him in a terrible way even by accident, you will never forgive yourself for not alerting the authorities. I'm thinking that the authorities probably know about them anyhow but at least you are on record.
As far as addiction, I have no doubt that similar to cigarettes, some can quit pot and some are seriously addicted. Every person's system and personality has it's vulnerability both physical and psychological.
I'm sorry that your son has struggled for so long and the fact that he is still smoking would tell you he is not clean. Hopefully, he will do better this week.
