Autox on the east coast?
 

I'm seeing a lot of events on the west coast on motorsportsreg, but nothing on the south east coast except http://www.goldcoastregion.org/calendar/

Are there any other hidden/unpublished events?

found it here
https://clubregistration.net

I know its a little far, but the facility is worth it ( outstanding facility) . Good course design, fast courses, good atmosphere.

http://gulfcoastautocrossers.com