Question About Dormant Account

I'm thinking about reactivating a secondary account I have but I'm running into some problems with the battlenet/wow merger thing.

The account I want to reactivate was created and lapsed prior to wow's battlenet merger. As such, I never merged the account with battlenet or created a battlenet account for use with it. Additionally, it was a trial account that I upgraded through the account management page so I do not have a code key. I'm assuming the links that I received in the email when the account was successfully upgraded from trial to paid pointed in the direction of a digital key. However, when I click on them now, I get an error saying that there is no wow account associated with the battlenet account and to add a game to go further. When going to *that* page, it asks me for a codekey that I don't have as it was not a physically purchased game but a trial account that I upgraded through the features on the wow account management page.

How would I best go about reactivating this account? What department should I send any emails and/or communications to regarding this issue? I'm assuming billing but from what I know of these types of communications, they're going to ask me for a codekey that I don't have.

Thanks in advance for any help/tips/etc that any fellow players or blues can give me :)