If we are talking about the same morgue where Striker imprisoned the mc. The back has grey panels or I'm guessing those containers they have in walls for keeping corpses. They create a sound when interacted with, in certain order they will direct power to the container that holds your stuff, you'll know it is the right order based on the sound they make.
I didn't have to spend three hours, at most 10 minutes, because I interacted with everything, got all the items to break out of the cage, found the note to Striker, read multiple descriptions while interacting with everything in the environment, then solved the puzzle. This supposed to be an escape room scenario.
So either your game is an older version which can have bugs or problems, or you are not interacting with every possible thing in the room to figure it out yourself.
