In this Area are 3 of this little caves. One with 5 lockers (wrong one) and if you look from the middle platform in the direction of this one, look a little bit left, a pipe is leading to another cave, but this one is also wrong.
For the right one, face the Bridge, from the middle platform. Than turn your head left until you see the pipe left of some stairs. Follow the pipe until it drops down, look a little up and you should face the right cave with the Kuria.

it's hard to see in the picture but it's in the crevace I think a little to the right of nyx's head

found the room, but not the kuria