This puzzle is specific to Emily and happens when you’re back in the basement after being in the trenches. In order to complete it you need to have picked up the Derceto Entombment Plans both A & B. Both can be found in the same room with the circuit breaker box.
If you look closely, you can see that each piece of paper has the room name on it. While that makes it easier to match it with the blueprint, they can be hard to see.
This picture has the names enlarged.
