...What?
I guess I'm not entirely sure what you're getting at with the dungeons and the Lakebed Temple. But there's been no concrete evidence as of yet to suggest the Gerudo are part of any "dark tribe," unless you want to count them as the dark tribe of Ganon's followers in the prologue of A Link to the Past (and even that's debatable). They're a mysterious desert-dwelling race of humans with a curious gender selection rate for their births, but they otherwise appear to be an ordinary people left to themselves. There's no suggestion of any cross between the tribe that used the power of Majora's Mask (which is barely elaborated on at all, even in the debut game) and the Gerudo, either. The most you have to go on is vaguely similar features between their bodies and architecture, which happens with all kinds of cultures across the entire Zelda series as a whole.
So, no, the Twili are probably not a mix of Gerudo and the dark tribe of Majora's Mask. Nintendo has never hinted at such, in or out of the games. It's probably best to drop it where it is.