Star-Sage, exactly. I’m not a mega ravenloft fan and I don’t know the minutiae of the campaign detail like I (sorta) do for Dark Sun, but . . . I guess one could make the argument that the Dark Powers of Ravenloft have a more varied criteria for those they draw into the mists than simply “horrible people who do horrible things.”
Although it’s important to note that Kalid-Ma is NOT the one the mists drew in. It’s Thakok-An that they chose.
I think the official TSR line was that Thakok-An got drawn in, and (maybe) the people of Kalidnay. Kalid-Ma, however, did not. The body of “Kalid-Ma” in Ravenloft is just a facsimile the dark powers provided. The real Kalid-Ma turned into a 27th-level dragon and rampaged until being put down by (iirc) Kalak, Hamanu, and Borys. His/her mind is currently splintered among the Orbs of Kalid-Ma artifact. Thakok-An still draws power as a templar, but the source is the Dark Powers, not Kalid-Ma. I might be futzing a couple of the details, but I THINK that’s accurate.
As of 4e, I think there was an article stating that Kalidnay DOES still exist, but as a city trapped within the Gray (instead of Ravenloft), out of phase with Athas proper.
I DO like the idea of a dynasty of priest kings drawing power from an incapacitated sorcerer-monarch, though. That DOES smack very nicely of the Egyptian mythos.