Refer-A-Friend Mistake

So a friend of mine has finally been convinced to play WOW.

i sent a refer a friend, and she played, levelling a toon to 10 before deciding to buy the game.

unfortunatly, she bought and registered the game with a different email address, depriving us of our experience bonus' and other perks.

It's obvious it was our mistake, but is there a way to fix this somehow? or is this a case of having to just move on.

thanks