I think that, before the shooting, Roth really had Michael conned into thinking that Michael could take over Roth's empire without violence--and that Roth would simply fade away to a retirement of playing shuffleboard and pinochle with all the other Florida geezers.
Yeah when Ola tells Michael "our friend in Miami will go along with.." - Michael looks like he believes it... but what was really going on in his head?
He just believed it because he wanted to believe it. He gave Johnny a fervently grateful look, clasped his knee and said, "You tell him that's greatly appreciated"--a rare show of emotion for Michael.
Ntra la porta tua lu sangu � sparsu, E nun me mporta si ce muoru accisu... E s'iddu muoru e vaju mparadisu Si nun ce truovo a ttia, mancu ce trasu.