The long-lost pre-drow like, aren't drow?
It's only the drow who followed Lloth underground and were cursed who got the dark skin, white hair, centuries of suffering to create their unique culture?
If lost civilisation pre-drow were around, they'd just be normal elves who live in jungles, have black hair, dark brown skin and memories of a fallen empire? I feel they'd be an elf sub-ancestry not a drow one?
From what I can gather, these 'other' Drow still got the curse when the other Drow did, but chose not to head to the Underdark when relations got sour with the rest of the elves and the elven pantheon.But I'm hardly an expert on the lore of Faerun.