I always wondered why that one scene never survived. And why they would have changed the story to have Michael personally shoot Fabrizzio.
As much as it would have been nice to have seen Michael personally take his revenge on Fabrizzio, I think that his having him killed, blown up, in the same way that poor Appolonia was killed, was in it's own way more of a satifying revenge. It was that "eye for and eye" type satifaction.