Unfortunately Georgia is one of the harder states in terms of tuition exchange programs. It’s part of the Academic Common Market, a coalition of southeastern states, but you can only study something if it’s not offered at a public college in your state.
The only things even tangentially related to his musical interests are the majors of Bluegrass, Old Time, and Roots Music at East Tennessee State and commercial songwriting at Middle Tennessee State.
One school that would come in right at budget is Western Carolina which has very affordable rates for out-of-state students, with tuition, room & board running around $20k. It also seems to have some popular music offerings.
Will your son qualify for Hope/Zell?