idk, I'm a little skeptical of the South Carolina pics you mentioned based on the weather we've had in the eastern US today and the timing of the aurora spread on that map you linked

I live in Ohio, and afaict from that map, it was only maybe briefly visible here around 8pm, which would have still been daylight in this timezone (same as South Carolina), and there were patchy storms across the eastern seaboard this evening.

maybe your friend was extremely lucky