Persons Unknown/WMG

They've been abducted by aliens.

 * Everyone including the night clerk.

It's all a variant on the Milgram Experiment.

 * They're going to keep offering the Sadistic Choice until someone takes it.

They are in Purgatory.

 * Seriously, someone had to suggest it. Especially after Erika's introduction. There is nothing to contradict it. Janet was kidnapped by someone rich and powerful and killed. Sergeant - KIA, Tori was kidnapped but later killed, etc and they all met on the other side. Why cameras, you ask? God loves reality shows, he wants his own.
 * It's possible that Erika just thought she was getting a lethal injection and simply was put into a death-like state long enough to get her out of prison. Regardless, if they are, it still leaves a lot of questions open.

It's all an elaborate Revenge game by someone with a lot of resources, even more anger, and still more patience.

 * Tom, the night manager, and the Chinese guys work for Mr. X. What could the others have done?
 * Graham - Pulled a Nidal Hasan or some variant.
 * Moira - Used to be violent and hurt someone Mr. X cared about.
 * Charlie - Really did kill his wife, or engaged in financial fraud.
 * Tori - If not she, then her father, offended Mr. X.
 * Bill - is Bill.
 * Erika - is Erika.

There's two groups. One is the whole conspiracy, the other is a group within it that's rebelling.
The guy that rescues Renby and Kat is also the guy that tried intimidating Renby in the first place (if this troper isn't mistaken).

Charlie didn't murder his wife. He just wanted Bill to get off his back.
Bill being... Bill, Charlie probably thought that the only way to get Bill to stop is to scare the guy into being a Jerkass somewhere else. So while he did Mercy Kill his wife, he didn't outright kill her.

The process (to use Tom and Joe's term for lack of a better one) is to test people for mental fortitude in order to fight some bigger hidden threat.
Having a CEO and an Ambassador's Daughter and others on your side would be useful. As well, Tori was eliminated after, essentially, breaking down.