Given those two reasons TB, yes, Roth would have had to know about the trip in advance. However, why go see Roth at all? Ola had just met with Mike on Roth's behalf and given Mike the go-ahead for the Tropigala takeover. So, why the arduous journey to meet with Roth?

The assassination attempt had just taken place, then Mike leaves. Mike didn't have much time to prepare, to make any arrangements. Ola was still in Nevada probably when Mike left. Ola would have had to beat Mike back to Miami. When was there time to make all these arrangements. And, again, why go to Miami in the first place?

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