So Red John had thousands of followers.... if that encrypted list is BA members, there's no way it even listed 1/10 of the members.  Also RJ had followers who were not BA members (outside of law enforcement) such as Lorelei Martins and Todd Johnson.  Its not believable if they caught or killed everyone even in 2 years.  When RJ died, did everything just crumble?  Regardless, they are still RJ followers out there and they would want revenge against Patrick.