You could have used the WoW forums, Customer Support category:
The Forum Support Agents there aren’t Game Masters, so they won’t likely be able to merge the accounts… but they will be able to tell you what your options are… if any.
This forum here is “… intended for 3rd party developers to discuss topics and provide feedback related to the public Blizzard Web APIs) used to create fan sites and other experiences.” – read Posting Guidelines: READ FIRST for details.