Why should Bruno give a shit about our wishes or expectations regarding Red John once he has given us Dead John already? Lightning never hits the same spot twice. The fake RJ was done before and we bought it with our mouths wide open salivating. So, there are 2 options here leading to the same conclusion:

1- Red John stays as Dead John and Bruno is an asshole
2- Red John comes back as someone else (you name it) which means Mc Allister was also a fake like the previous one and Bruno is still an asshole for doing us the same trick twice.

So, any of us may like any of the above options but in the end, there's only one thing that remains the same: Bruno is an asshole. When I think like this, I feel that I will be OK with any kind of ending to this series. Yeah, I think I found my closure...