His name never really changed, it just can be pronounced two different ways. To add on to what you're saying, Johnny Sindacco also pronounced Salvatore's last name with a long "e" sound. Toni's last name pronunciation changed a bit, too since in the mission The Pick-Up in GTA III, Claude was reading Toni's note, Toni was narrating and at the end, he pronounced his last name like "Kipriani" but in LCS, everyone said "Cipriani".