Dream?

I was originally going to post a ton of questions, but after reading my questions, the only conclusion I can come up with is that THX was driven insane or killed after he was detained, which is when the story pretty much stops making any sense.

When they examine him, one of the lines reads "reusable parts". That looks like they plan on killing him to reclaim his organs (or death is a very possible side effect of the experiments they are about to perform). Then the two guys experimenting on him are arguing. Apparently, the numbers went too high at one point. Maybe that drove him insane and everything after was his "disillusioned" dream. The only reason I came up with this theory is that the story made sense up until this point. After this point, little makes sense:

1. Roommate is pointlessly ushered in so they can have sex one more time before they kill her. If they wanted to monitor their deviant sexual activities, why kill her shortly after only one encounter?

2. A robot guard is overpowered by a human and is easily beaten and destroyed.

3. Endless white detainment room with a non-working security system with an unlocked door that leads to every conceivable place imaginable, including a huge busy area and areas that should be secure.

4. They meet a man who says he knows the way out. Yet, he is there. Waiting for them to arrive before leaving. If he knew the way out, why was he still there?

5. The man also says he's a hologram. Yet he has knowledge of many things (except how to drive), proceeds to touch everything in site, and even eats! Perhaps he's not a hologram as he says,

6. And the ending. Why is there a ladder there? Why is everyone living underground if you can just climb out at any time?

It seems all of the things that happen (sex with roomy, interactions with SEN, black man hologram) are all things that he encountered shortly before and would be fresh in his mind as his mind deteriorated. Of course, The solo scenes with SEN later on make no sense since THX isn't present, but it makes a lot more sense than weak robots guards, detainment facilities with no security that lead to random locations, a physical, hungry hologram, and an accessible forbidden place.