It does not have to be for transfer credit. Could just be an addition to his resume. It is just that at this late moment, acquiring comp sci skills would probably be a better use of his time than a grunt job unrelated to hisfuture career, unless he needs to earn money.
One of my kids did a year of organic over the summer btwn freshman and soph because they couldnt get a clinical job. Wasnt required for their major or minor, but was a med prereq. Another did intensive foreign lang study, didnt need the credits. Just putting it out there as a potentially useful summer option, if no relevant internship found.