So what lies south of devil’s crossing and will we ever see an expansion covering that side?
Very old stuff and no, never.
Well there is not much there. Because of the default cameraview, they decided not to use that area.
I remember Zantai or Grava saying that most likely nothing will be there as pacing south doesn’t feel right. Something like this, I don’t remember exactly what he said.
I still want that, though. Running east, west and north is boring already. 
That is unfortunate. I wouldn’t mind if they add a little something along the size of the area east of the mud flats(forgot the name). Would be nice to have something there but understandable if pacing suffers because of it then might as well have nothing.
I’m not expecting another expansion, but if it were to come out it could easily be south of DC.
Just make players move towards DC from the south, FG works the same way.