i think they have made changes to the way they process this information and many tickets have been canceled to get it sorted out the "right" way. Been seeing a lot of threads like this today. There was a Dev post 2 days ago acknowledging this issue and providing a swift resolution. You can find details here in the official response. Hope this helps, if it does can you update your OP with this link so others can get their accounts working too? Thanks and good luck!

I understand your frustration for accidentally registering a second account or not understanding the account linking qualifications, it was a little confusing. Please understand that you are not alone and they are dealing with a metric shit ton of issues at the moment with requests and calls coming from all over the globe. There is only so much they can do.

Also this post I linked may be directing you to the same form but the post itself is only 2 days old. Old tickets may have needed to be canceled that were getting backlogged in from the SE side of things and now that this form bypasses SE's customer service and goes straight to the FFXIV team, your issues should get resolved quicker, I hope. If things get resolved can you please post back here? I would like to make sure this does help people get their issues resolved. I have subbed this thread and look forward to some positive news. Again, good luck and I hope you are up and running ASAP. As just another forum poster this is the best I can do to assist you in your problem.