Like someone said and I believe are correct, the Rizzuto faction always had a Calabrian faction. I'm not sure if Arcadi ran that side until Di Maulo was killed when Vito was released. I don't think Di Maulo was that active anymore mind you, but I think more would have easily followed him before they would Arcadi.
I do find it crazy Liborio is with him unless it was a set up? If it was N.Y. I could believe something like that, but most of the time in Montreal family followed family no matter what.
Too bad Del Balso and Arcadi were reported back to prison because things were just now getting interesting again. I imagine things get quiet for now until they get out or go back to a halfway house.