"Contagion" mission -- does it dead-end or am I missing something?

In tier 4 of this Carpathian Fangs mission, called ‘find the source of the filth,’ I go to a red-circled area on my map, where online sources say I’m supposed to find a tunnel but there’s nothing there. And when I reach this area, which is quite small, the mission instructions that guided me there don’t update.

I’ve had a few obvious bugs, and some things that seemed to be but were just puzzles, like where I had to be in spirit form to perform some function, but this one doesn’t fall clearly into either category. Two sources I’ve consulted on the mission, Unfair and CryGaia, both talk about it as if it’s pretty straightforward, so I’m not sure what to think.

I’d appreciate if anyone who’s done the mission could let me know their experience with it.

You’re looking for a filth hound named The Stalker in Darkness at (830, 560)
(source: http://legacy.tswdb.com/missions/carpathian-fangs/contagion#tier-4)

just go down and down and down, there are parts of the cave system that look built up (akin to the roman baths nearby). get to those, you’re entering the right area. another tunnel past there, with a champion zmeu in a room off to the side, and ahead of you is the stalker in darkness. point your cursor at stalker, mission updates, you get a fight on your hands

Moved thread to #secret-world-legends:swl-discussion — Not a tech support issue.