Stubhub and Ticketmaster don't have any agreements like this; they hate each other. Stubhub does not "verify" you have tickets, but they keep your cc on record, so if you can't make good on tickets you've posted on their website, they will buy comparable replacement tickets from somebody else, and take the difference from your credit card.

If you're looking for ticket info, it is easy to get for the secondary ticketing market. Get in touch with ticketnetwork, they have an XML feed of tickets from ticket brokers from all over North America.