This scene was abandoned, in tandem with the later one showing Fabrizio's murder. Michael's memory in identifying his first wife's killer after more than a decade recalls his father's unerring ability to track down his parents' assassins when visiting Sicily.
This scene would appear right after Neri's humiliation of Klingman, and before the scene in Part II where Michael finds Anthony's drawing on his pillow. We know that the murder occurs in Buffalo because in the scene "Fabrizio Located", Al Neri states that the Sicilian has been found there.
Za EX FILMOFILE Anamnesis