Clearly Gambino had no issue with it being done nor the other bosses. No move was ever made against Persico. Colombo's sons did not have the backing inside or outside of their family to step up. Persico's crew was the only one to move into the vacum. Gambino had pulled his support of Colombo, clearly Carmine Persico set emmisaries out to the other families or the acting bosses he put into place would have been dealt with. If Gallo was behind the hit why didn't he make a move against Persico(whom he has a violent history with) or the Persico acting bosses? If he had the balls to hit Colombo, he would have made the move against the Persico crew as well.