I am in the B2 level of the building. It’s the boiler room with all the pipes. I can see the key up in a higher level near where the ghost turned the water on but I can’t reach it. Bone of the pipes get me there. Turning the water on and off seems to do nothing. What do you need to do to get up to the pipe where the key is?
If you look closely at the wall you will see there is a piece of cloth just below the valve that turns the water on and off. Suction the cloth and rip it off the wall. This will reveal a second green pip, next to the one that is already there that you can use with Gooigi to get up to the platform that contains the key.