There are many different options, depending on what he wants.
Does he want to go the college route, or would he consider a 2-year conservatory program, possibly one with the option to earn a BA through a university with an articulation agreement?
Is he interested in taking a gap year, training, working, and reapplying to a slightly different list of schools with less stringent academic requirements?
Does he want to go to a school that has more stringent academic admissions requirements, and take some GenEds at CC, and then reapply (the challenge here, as you mention, is that he may lose freshman status at many schools, so it could change the admissions requirements and timeline)?
There may be still be some schools accepting applications, and with auditions. Does he want to add a few schools to his list?
Broadening his search, either this year (or next, if he takes a gap year) could yield some schools he might love that he does not yet know about.
All that being said, it sounds like he still has schools left to hear from. As Yogi Berra said “it ain’t over 'till it’s over.” This is the hardest time of year… some decisions in, some pending, auditions over or winding down, lots of time for contemplating and second guessing.