Think along the same lines of Vito's killing of Fanucci... After that, everybody knew who Vito was in the neighborhoods and eventually NYC. He was well on his way to his future empire.
In Sicily, Vito kills the powerful Corleonesi Don Ciccio thus cementing his reputation, power and station. The last people to see Ciccio and his bandits alive were olive oil importers from America. Right next to Ciccio's body is a Genco can. So, his muderer isn't known or even suspected?
Fabrizio acted like the "Corleone" name was Smith or Jones when translating. Wouldn't the entire island of Sicily know the name of the man who killed Ciccio years ago?
