LOL, I never looked at it that way before. I actually found that guy twice.
Sindel's ring and Ashrah's sword seem to be two that we can't get a definitive answer on. Sindel's ring in particular is worrying some people because it may be that, for some reason, you can only get it shortly after Mileena asks you to get it, and after that it's gone and you're screwed. I know I don't have either one, and I don't feel like starting ALL the way back at the beginning with a new profile just to do that.
Personally, I'm wondering if it's a glitch that Midway overlooked. I really hope not.

the kriss is in the neatherealm near noob saibot outside the city
and if that doesnt help just go south after you leave the city
its by the lava river