The Atlantean Foundation was created by Alachia (under another name, obviously), the former queen of the Blood Elves (also former Queen of England, IIRC). The Black Lodge, however, could very well be of Theran descent, or descended from the Denairastas clan.
The dragons and IEs called a truce at the end of the 4th world, a truce that has (mostly) remained to this day, other than a bit of civil (if not friendly) gamesmanship, until Harlequin declared war on Ghostwalker.
Unknown what Theran colonies may have survived to be discovered these days. Some may have simply 'reverted' to normal ancient ruins, while some may be in astral space or other such things.
There's a reason Aztlan looks the way it does. That reason is the Smoking Mirror, which may very well be a Corrupted (or, worse, Horror-touched) Great Dragon.
The true drakes did not rebel. They are more closely bound to their makers than the IEs (and have a limited life span as well).
Verjigorm did not show in the 4th world, AFAIK. It is still FAR too early to talk about him in the 6th.
And as for your last question? Not going to happen.