The guards are even more obnoxious in the novelisation.You are correct and I'm not sure why I remembered that line as being the guard's especially when I've only seen the movie about a thousand times.
But going back and watching that clip now I do see some merit about Kirk testing him, since the guard gets a funny look on his face and hesitates before he says "Two minutes". Then again, I also got the impression the prison guards just act like a bunch of obnoxious smart-asses to any visitors given one was so quick to threaten Sulu and ridicule his height (which also doesn't seem very enlightened for a society supposedly accepting of physical differences).
One of them...cheats at cards!!!
