The fact of the matter is, it does not matter who you pick. I doubt the person they pick, you will be like "oh yes now I see, that makes sense". As I watched the episode where Jane shoots RJ and it turned out not to be RJ the next episode I realized then that the writers can do whatever they want, it is up to them. They could say your mom is RJ. It won't be like they will show you clues that was in previous episodes. If the did then it would be Rigsby. In the episode where Jane shoots RJ. They were going to do away with RJ but for some reason they changed their mind and pulled a rabbit out of their hat and said oh that was not RJ. How would RJ know to send someone else to the mall and have him claim to be RJ and know what his daughter hair smells like. That was supposed to be the real RJ but they backed out for some reason. Like I said the writers could say RJ is the tooth fairy and that is why he draws a smiley face. Don't look into it deep because its not that complex. If you look at old episodes Rigsby was never around when RJ was up to no good. So that is why I thought it was him but it will probably be your mom or mine, not sure.