In the one & only Gangster BB dinnner we enjoyed together, Turnbull explained beautifully how in this meeting, Michael played Frankie like a violin.
The surprise visit & brief outburst followed by gentle, respectful prodding & nostalgic references to his father & the old days were not necessary, as Frankie would've at that point followed his Don's orders anyway.
But intimidation and submissiveness was EXACTLY what was needed after all that defiance and disrespect shown at the Communion party.