I'm of the opinion that he did, personally. Fernandez wasn't killed for running his mouth, everything points to him being killed for refusing to meet with Vito and trying to play both sides of the fence. If we're of the belief that placement means something in this lifestyle, the guy had Fernandez seated right next to him over his own kind.

Although I do suppose he could've been leading both on and taking parts of their earnings, but if that were the case, why not just kill them and takeover their businesses, he did it to everyone else, what made Fernandez & Desjardins any different ? Considering the association with Vito made them bigger than what they were without him? It just doesn't make much sense to keep them around and so close to him, when he really didnt have to. Especially in Desjardin's case, because it turned around and bit Vito in the ass.