Although I agree that rats are not a big concern, the potential problems go further than dons, like Massino. Sammy the Bull, Gaspipe, and Sal Vitale were underbosses, who accompanied their bosses to commission meetings. At the time, it was Chin's rule that only bosses and underbosses could attend the commission meetings. And as far as I know, nobody was frisked.

Over the past decade or longer, it could have been really challenging to have commission meetings, which included the 5 families. The Colombo's Persico, the Lucchese's Amuso, the Genovese's Chin, the Gambino's John, John A, and Peter Gotti, and the Bonanno's Massino were, or are still, in jail. There might have been a time (probably around 2004), when the bosses of all 5 families were locked up at the same time.