Quest takes place in Vashj’ir -> Shimmering Expanse -> Damplight Chamber
There are 2 objectives: Fend off Naga attack & Fathom-lord Zin’Jatar defeated
except, whenever attack stops and Zin’Jatar appears, the attack just continues and he is immune to all attacks while not moving in the water from where he appears.
I’ve abandoned and rejoined the quest several times with the same result. the quest cant be completed like this.