[andrewas]

Nope, he should be fine. Normaly id recommend slaughtering Elhan and all those elves for daring to attack a bhaalspawn, but in this case I dont think you can finish the game. Its possible you hit one of the elves accidently at some point, or it might just be a bug. In any case the easiest thing is to load a save from before you met him and replay that section.