I still think it was an attempted murder-suicide. He wanted to take some cops with him.
We need the handwriting analysis of the note with the detailed instructions for the heist. If that's in his handwriting, or his mysteriously dead friend's handwriting, then I'd take that as confirmation.
But this sure is a weird one...
If the pizza guy was the patsy in this, then I would speculate that it was the manner and voice used by his 'controller', as well as showing him the remote detonation device (we assume there was one?). If I saw a collar like that, and one or more guys locked it on my neck, showed me other devices,etc. and pointed me out the door and told me to rob a bank, What would I do?
(1)Rip the collar off and head to the police department
(2)Do as they said, assuming anything that complicated was probably real
METHINKS PROBABLY number TWO.
HOW ABOUT YOU?