I don't believe those rumors that the Violi's are out of favor with Buffalo. Bifulco and Joe Violi are still tight.

Yes, there is evidence of Buffalo and Canadian mobsters knowing each other before the Magaddinos showed up in Buffalo.
Erie, PA still has a few former Buffalo associates but they are retired. Raymond Ferritto Jr, who's father killed Danny Green, is not an associate to any family.

"I have this Nightmare. I'm on 5th avenue watching the St. Patrick's Day parade and I have a coronary and nine thousand cops march happily over my body." Chief Sidney Green