
Garretmander |

None that I know of in official information.
Partially because until the events of the second darkness AP, drow were unknown at all on the surface. They were the elves dirty laundry.
More likely there would be individuals doing business near the surface at major access points between the darklands and the surface. There's definitely not any large 'noble' or multi-generational family on the surface.

Garretmander |

Rogue drow alchemist cabal that left the big cities to go near the surface and work their trade for greater profit?
There was a sort of similar minor plot point in another AP
Serpent's Skull:
A rogue drow captured by the antagonists of that book. He had fled through the darklands after stealing a few secrets of fleshwarping and was planning on selling them.