CJ foreshadowed the twist earlier in the movie

WHen he was talking to his friend in the mall about the whole plan and setup, he mentioned something like "It'll be someone that the cops have nothing to go with, like a random hooker or drugdealer etc"

Granted I didn't know the twist and didn't see it coming, but looking back it kind of makes sense. Cause when the whole scene was going on I kept thinking to myself "So just how do you find any random murder victim?" I mean even when it happens odds are the investigators are going to be at the scene beforehand and collect all the evidence and so forth. In other words, CJ said this because he basically knew it was going to happen (cause he did it obviously). Fittingly so, the victim was indeed a hooker, hence why he said it to his friend.

Like I said, I didn't see the twist coming, but looking back it at this scene it pretty much foreshadowed the whole twist.