As above. Could be, could be otherwise.
As a community mental health nurse for adults I knew quite a few people whose history of impulsive overdoses or overuse of sedatives meant that it was sensible to pick up each day’s at the pharmacy. None of the people i had in mind took methadone or even had a significant history of illicit drug use, this was about low mood (or rather disregulated ie not low all the time but very fragile/brittle) and risk of overdose. I work with children nowadays who have parents for that sort of thing, but AFAIK this arrangment is still the case for loads of people round our way with no methadone involved.
Whether its that or indeed opiates/methadone, some stability, realistic/consistent/reliable friends and family, and a secure base of sorts will be very helpful to him. You could be a part of that OP.