For some reasons i believe its Patrick who killed Panzer (San Joaquin Killer). Before that episode, every one believed RJ was killed by Jane. No point for RJ (if he was alive )to reveal his identity immediately after the talk show.
he is always hiding isnt it ? its good for RJ to stay even low from FBI after fooling around with Jane into killing of Timothy Carter as RJ.
Why will he reveal himself to kill him ? when he has a chance to operate even low.
From that episode we know that PJ really hate Panzer and wanted to kill him.
