I´m not sure if this theory is good for you but don´t click "unlickely" only because  J.J. LaRoche isnt on the list. Bruno Heller said :- "You can trust the list" but ... which list? 
-The newest one or the older one? Because in the older one LaRoche was there. Well , lets start.

We all know that LaRoche cut a tongue (I don´t remember who was the victim) and we know WHY. Because he rapped his mother. So lets look at the murderers:

8 unnamed suspects: Dunno the reason.

Jane´s wife and daughter: Patrick Jane mocked him.

Jared Renfew: He was going to blame Red John.

Emma Plasket:Dunno reason

Sam Bosco and his team: He sent Rebecca to kill them because he knew that Bosco had important information and he took his case.

Rebecca: He knew that Patrick was going to take information of her.

Towlen Morgen: He killed him because he wanted Jane to find Martinez body.

DON´T YOU SEE IT? All the reasons are similar that the reason of the tongue. IN ALL THE REASONS THEY ARE GOING TO REAVEAL HIM / THEY MOCKED HIM / AND TOOK HIS CASE.

TOO OBVIOUS