This is my guess. The bosses of the other familys say no to carmine passing the thrown to his son allie whose doing life. You cant do that. Thats showing zero respect for the rules and anyone else in thaf family. Just name someone else whose free thats gonna do whatever allie says anyway. A figurehead. Barney crea and gambino probaly said nope. Find another cousin. In the 70tys they named dibella as boss but it was carmine behind bars calling the shots hed probaly named his brother but he had only recently been made.