MSC has to follow the “Americans with Disabilities Act”, so hiring by MSC with one eye shouldn’t be a problem.
There is an active drug testing program, the MSC is not a drug culture.
They will be a lot of sea time, hoops to jump through, dollars to spend and classes to sit through between QM on a 110’ and 3rd mate.
The SRS program has a recruiter and a pre-training fitness program in Norfolk, VA before attending Navy SRS school.
Stay in the USCG.