The problem with that, though, is that sa far as anyone knows from the outside, LA is perfectly normal.
Personally, I find that hard to swallow if the assumption is that it is merely a glamour. LA simply has too many connections to the world.
Mark my words now, there is something more to it.
I think it is the other way around. I think the Fang Gang being in hell is the glamour, along with Angel's humanity.
My suspicion is that Gunn has become aware of it and is attempting to reverse it.
It might be that he is not even be a "true" vampire himself and everything they see is illusion.
Yeah, they do seem to have a cell situated in easily accessible zones for maximum coverage.
LA (west coast USA), Cleveland (mid-USA), NY (east coast USA), Scotland (west Europe), Italy (east-Europe), Japan (Asia), Rio (South America).
Taking that into account, and the few core members of the gang I can see Wood as overall commander of the USA since he is in the central position of the USA.