My theory is that Bob is killing the people on the fake list, believing one of them to be RJ, and once he gets wind that the list is fake, he kidnaps PJ in order to try and get the real list. Realising his career is pretty much over, he goes all out to get the list, comes close to killing PJ, but at the last minute, the real RJ comes in, kills Bob, saves Patrick, much like Red Sky in the Morning, but this time, he doesn't speak or uses a different voice, something that would throw the viewer off. Either that or pigeons will somehow feature again.

Kirkland it would appear is out to get RJ, but in a far more aggressive fashion than the CBI, which suggests a personal reason, much like Patrick. My theory is that RJ killed a relative of Kirkland, and it's taken him this long to gather information, and unluckily for him, he's probably going to meet his end at the hands of  the real RJ, much like Lorelei Martins did on her revenge quest.