I say it's all the con. There is no way Will is really going as dark as he needs Hannibal to think.
He may well have killed Randal Tier in self defense and maybe he
really did enjoy it while fantasizing it was Hannibal. Who could blame him about that? I'm just convinced that he called Jack Crawford right afterward and Jack is in on the plan to get Hannibal to reveal something. Randal's attack would have been enough to convince Jack. Another of Hannibal's patients is dead and a killer and went after Will? The only thing about this theory that strains credibility is the idea that Jack would be okay with the mutilation and fake crime scene, but under these circumstances I could see him going that far after being deceived so completely multiple times. He may have just given Will the go ahead to do what he needed to do.
There is also no way in hell that Will actually killed Freddie Lounce. The meat he ate with Hannibal must have been that of Randal Tier. He has now convinced Freddie to be part of the plan. She could be tied up until it’s all over, but I really doubt it.
The reason Jack has to be in on the plan is that it would have been the only thing which could have convinced Freddie that Will wasn’t going psycho for real after seeing his freezer of long pig.