Nobody beside the dealer has access to the database of radio security codes. That said, the people at the dealer you spoke with are a bunch of crooks. They're supposed to provide that information for free (but you have to visit in person, with proof of vehicle ownership).
1998 BMW 328is
1966 Pontiac GTO
2007 Subaru Impreza 2.5i 5-door
View my photos: Caught in the Wild