[SPOILER] Stuck in Chapter 6

[Aurelessa]

I've succesfully solved the puzzles until now without the need of a guide but I'm stuck on part 6 for an hour now (this is a hard sting to my pride, I'm feeling like an idiot already). I'm in control of Regis and there's an assault force against me. I took care of two of the three (that I'm aware of) soldiers.

The first soldier went KO with the jolt gun after I messed up his camouflage the second went KO with a good ol'fashioned molotov cocktail.

The third soldier, however, is getting me mad, I already got him covered in water by stuffing the drain in the upper level (locker room) but it's beyond me how to proceed further. I tried to use the jolt gun with the water which is the obvious thing and it tells me that that wouldn't do anything, I also tried to use the jolt gun against the uh, wet soldier and Regis says the gun is out of charge. So, I have to charge the gun?

I took a metal disk from the bots in the factory and polished it, but it appears that this item does nothing related to the problem I have at hand since I can only hang the disk, polished or otherwise, in the robot arm that I cannot control with the panel. So I gather (perhaps wrongly) that this is a puzzle I would have to solve AFTER I defeat the third soldier.

I'm desperate, I'm at the point of just trying items at random. What I have to do? I'd appreciate a hint (a gently nudge?) more than telling me straight what I have to do. But really this whole thing seems too obscure to me.

[str4hlemann]

You probably have solved it by now. Still, if not, here's some nudge.

You deduced correctly that the robot arm is a puzzle you gotta solve after dealing with the third soldier.

Wet + Soldier also leads to something most obvious. But it is not the jolt gun. Why not take a look at the direction that big industrial laser in the room is pointing in.