Vin Scully doesn't exist in the Sandlot universe!?
At the end of the movie, the story flashes forward to Dodger Stadium in Los Angeles, where a now adult Scotty Smalls is doing play-by-play of a now adult Benny Rodriguez playing baseball for the Dodgers.
Now, it isn't entirely clarified if Scotty is doing commentary on the radio or television, so it isn't like Vin Scully was the only play-by-play announcer for the Dodgers. Nor is it clarified that Scotty is supposed to be the primary Dodgers broadcaster, but I noticed that Scotty appears to be working by himself (much like Vin Scully tended to do) instead of working with a color commentator.
https://en.wikipedia.org/wiki/List_of_Los_Angeles_Dodgers_broadcasters