There is a way of accessing the routes and route groups of a particular virtual device programaticaly. You will need to have session manager server installed.
1) Create an activeX session and connect to the session manager server 1.0.
2) Select "IInstrSessionMgr" for the Automation refnum
3) Enter your virtual device name in filter
4) Select "ReturnRouteGroups" or "ReturnRoutes" for Flags
5) Enter empty string in Category
6) Change the Variant to data (Array of string) to get the names of routes or route groups.
Regards