Possibly broken quest "The Deathstalkers"

NPC “Astor Hadren” for Rogue class quest “The Deathstalkers” (on lvl 10) is missing.

Wowhead quest page:

NPC page:

I tried to find him for two hours without success. And I never saw his dead body.
I asked other rogues on this, they told me that they could not find Astor for several days, and also never saw his dead body.
It doesn’t look like he is killed quickly, as there are just a few rogues in the patrol area of the NPC (2-3 people).

Could you please re-check this quest?