I am very surprised if he can't find a job, as an American, in DC, with 12 years of C++ experience. Sure companies aren't great at assessing open source experience, but there is one area its easy to find a job as a dev: work that requires a clearance.
St. John’s college is a great place that draws a special type of young person, but its graduates are not very STEM-legible. As far as I know they still offer no choice of major & no hands-on classes — just the great books.
Of course that makes this person’s skill all the more impressive.
Not everyone will take a job that requires clearance because they are usually "defense" related.
Also, acquiring said clearance is not always straightforward, even if you lack sufficient scruples to be willing to pursue it in the first place.