As of now, the theory that Verduci was killed as part of a fued between the Figliomeni and Coluccio clans still seems the most viable to me.
If it was in any way linked to Rizzuto in Montreal, perhaps that than also means that Coluccio had good ties with the Rizzutos. It would make sense given the fact that Coluccio is the son-in-law of Bruzzese and was supposedly close with Joe [BadWord]. Something to think about.
"It was between the brothers Kay -- I had nothing to do with it."