I got the Dialga by loading up a ROM, inputting the Wondercard file for the event that I got from here (
http://projectpokemon.org/events/en-V.php) and getting the Dialga, with its own unique, game-generated PID. Then I traded it to my real cartridge over fake WiFi. Can't wait to do the same for the next two events.
Didn't even have to go to Gamestop. It's my day off, and I'm not leavin' the house if I don't have to, because I'm a lazy shit.