This cave echoes like crazy. Better put the gun away and keep quiet
The Evil Within ITEM MANAGEMENT – Achievement / Trophy Guide
In Chapter 8 you are not allowed to shoot any of your weapons. Run past the first enemies into the next room where you have to open the gate. Your goal is to lure these two enemies out into the starting area. Stay close to them and go back. As soon as all of them are in this room you can go and open the gate. They will only follow you for a short distance so this shouldn’t be too hard.
After that you only have to complete the chapter. I think there were 1 or 2 more enemies that you encounter and you can dodge them easily.