I don't know if you figured it out already but I'll reply anyway. I live in central SC so I'm not in the general vicinity and don't know of specific schools that are offering it near NITOC and BJU. The College Board's instructions
(as far as I understand) are:
College Board wrote:
Home-schoolers and students Whose schools do not Offer AP
If you are a home-schooled student, you are preparing on your own, or you attend a school that does not offer AP, you can still take the exams by arranging to test at a participating school or authorized test center (for students outside the U.S.). Call AP Services for Students no later than March 2 to get the names and phone numbers of local, participating AP Coordinators who have indicated a willingness to test outside students. Then contact the AP Coordinators identified by AP Services for Students no later than march 16. When calling AP Coordinators to arrange testing, be sure to tell them:
Ꮀ you are trying to locate a school willing to administer exams to home-schooled students or students from schools that do not offer AP Exams;
Ꮀ which exams you plan to take; and
Ꮀ if you have a documented disability that will require testing accommodations at the exam, and if you have been approved by the College Board to test with accommodations.
Once you locate a school willing to administer your exams, that school’s AP Coordinator is responsible for ordering your exam materials, telling you when and where to report for the exams, and collecting the exam fees, which may be negotiated to recover additional proctoring or administration costs. That school must administer the exams for you; the school cannot forward exam materials to you or your school for handling.
You have to come with a state-code for homeschoolers. I know for the PSAT in the past I've tested with others who came from outside of state, but the procedures may be a bit different.
Also, the International part of the College Board says
College Board International wrote:
If you attend a school that does not offer AP, contact AP Services at +1 212 632 1780 or email@example.com
for assistance with locating a testing location near you. For more information on registering for AP Exams, visit Registering for AP Courses and Exams (not in China or India).