Phoebe says that the slumlord wants to see her and Cole, but later, the slumlord is showing Cole the tape and is about to leave without waiting for Phoebe. So did he really want her there or was she supposed to come just to find out that Cole killed him? Speaking of which, Cole was obviously going to kill him from the beginning. It was anticipated. So he could've done it and Phoebe would never have any knowledge about the incident to begin with.