Michael's "perjury rap"Michael probably sent for Vincenzo the moment he heard that Pentangeli survived, and before he summoned Fredo..
My take too since Michael
already knew that Frankie Pentangeli was alive and was being prepared in custody to testify against Michael – the committee's secret star witness
before Michael went to talk to Fredo -- arrangements would have
already been put in place,
1. to bring Frankie's brother, Vincenzo over or
2. Vincenzo was already on a plane, to the Senate hearing