I think that Kira Tinsley's murder and Brett Partridge's missing arm skin ties in.

The real RJ doesn't have the tattoo. The whole dot tattoo clue was intentionally leaked by RJ to lead Patrick and the CBI to root out RJ's rivals, the Blake Society, for him. What Tinsley saw in the few moments before her death was actually Partridge's arm skin attached to RJ's body (eww). RJ was bringing the group to CBI's attention more directly, since past attempts failed.

Think about it. If RJ was really a member of the Blake group, why would he need to bug the CBI? He could just call Bertram and find out everything he needed to know.

By the way, when I say "rivals", I mean that RJ had been using, manipulating the Blake group. He was never a member, he was just using them, posing as one, but when they discovered it, he decided to get rid of them through the CBI. Maybe even the bugging was a trap, a clue that lead directly to Tinsley, to Tinsley's murder, to the red dot clue, to the Blake group. Red John has been manipulating the situation the whole way.

Sadly, this doesn't mean I know who Red John is. Haffner is the surveillance expert, but he's supposedly dead. It looks like McAllister in the promo for the next episode, but I doubt it's that easy. It might not even be as easy as this theory. I'm just throwing this out there.

The weird thing about all this is how now everything looks like a clue. We're all looking at everything, and I think Heller intended it. We're jumping at shadows. "THIS MUST MEAN THIS." So I have to admit that my own reasoning is flawed. I thought this whole idea up while drifting off to sleep, so I may noto have been thinking clearly.