What might be credible? In '57, Genovese arranged for Anastasia to be assassinated, and for Costello to retire after his skull was grazed by a bullet fired by The Chin. So, it's credible that the meeting was held, in part, to anoint Genovese as boss of the family formerly headed by Costello, and to bless Gambino as Anastasia's successor.
The most plausible reason IMO.
Another possibility: to approve drug-trafficking. That might explain why Bonanno wasn't at the meeting (his close associate, Gaspar DeGregorio, was). Bonanno earlier that year had set up his own drug trafficking apparatus with Luciano in Sicily, so he and Genovese might have been rivals in the drugs business.
The Mafia was involved in drug trafficking since the 1920s so why would they needed to approve it in 1957?
Did Lansky blow the whistle on the meeting? That piece of BS was touted by Rich Cohen, in his BS-laden book, "Tough Jews." I doubt that Lansky would have bit the hands of 80 or so dangerous men who fed him.
Indeed. If Lansky ratted them out he would have been killed for it.
