No Remorse (ASK) Mission 4 Secret Room #2 ?

[xor01]

After Cordova sacrificed himself, you proceed and enter a turbo lift. The lift take you to the "green slime room" (loading new map). Here's the description from the walkthrough:

"One area of this level is a network of bridges crisscrossing an enormous vat of green slime. If you can jump down to the pipe spewing fire and twist the valve on it, you will will lower the slime and be able to enter a secret area."

I already done the above and found the secret room, no problem with the above. BUT, my problem (and question) is:

On the last room with the lift to load the next map, if you go outside and walk to the left, there's a small elevator that can take you down to the water level, but I can't find a way to make the water gone.

 

[The Silencer]

I think it's a red herring, I've looked around there quite a while. It's like a part of the first mission, where you can see an area through a camera, but can't cross the slime get there.

 

[xor01]

I think it's an unfinished secret room because if you use "Hack Move" cheat and remove the water "block", you can see there's a dry base below it (if you move "normal water pool", you will find another water pool below, not dry base).