I thought of another possibility: if he enrolled at a university that will allow him to skip or test out of the introductory CS courses, then this will also save time, though he’d still likely need to take non-CS intro courses such as calculus, physics, and a variety of liberal arts/humanities courses.
There’s also the possibility of applying to universities where even the intro level CS courses are quite rigorous and where there’s an expectation, tacitly or explicitly, that CS students have prior experience. Berkeley’s CS 70, for example, is ostensibly an introductory course on discrete math and is required in the EECS program, but it’s much more rigorous than the standard introductory discrete math course taught at most other universities.