As a ranger who's accompanied our guild paladin on a number of corpseworm clearings, I would/will never attempt a quest for myself that has this kind of a bottleneck built in. A week respawn for a 2% chance at a quest drop would be a deal-breaker for me from the get-go. The fact that a small raid force is required to clear Lurk/corpseworms compounds the problem. The fact that multiple people are after these same targets every time they spawn makes it even worse.
I support an easing of the bottleneck for this quest.