Patrick Jane already know it's not McAllister cause he doesn't talk smart like red john and you remember when Jane killed a guy in season 4 i think people though it was red john then when he start killing again turns out it wasn't him , same thing gonna happen here , the black guy from the FBI also from RJ guys , Because Reede Smith told us that they hire Federal judges and FBI agent who need there story to be covered , which means the black guy has been gifted the Federal court order to bring jane team down before it's to late , so RJ send McAllister to make Jane stop looking for a while 

we all gonna see McAllister is not RJ it's Brett Partridge because ...

because McAllister faked his death and no one said something even Jane and Brett i'm sure can do it more better then him cause his RJ , and Jane didn't check his body when he died inside the house because if he did he won't find it and RJ will know that Jane know his alive ...

that's my theory and sorry for my bad English i try to make to clear as possible and thanks for reading .