Kasimir Velikhov

From Adrian's 'Persons of Interest':
A Dusk Elven leader from the settlement on the hill with a Vistani camp on top of it, Southwest of Vallaki. He told us about the decline of his people. How Strahd killed all the males after they murdered Strahd's wife.
They murdered her because she was a Dusk Elf, and fell in love with the 'Devil'. Was he a devil then? Or did the murder of his wife turn him into one? Regardless, he spoke of a powerful artifact in the Amber Temple. The means to restore to life one who has been dead for centuries. One such as his sister. The same woman who was murdered for marrying Strahd. She currently resides in Castle Ravenloft, as undead.
I was not sure about this man, motivated by the need to restore his race that he would bring back from the dead a woman, his own sister, that was murdered. Surely she should rest after all this? Why don't they just bugger off and marry into humans or something. Who knows, not our problem. That artifact could be useful though. Madame Eva did mention Amber Doors...