And GDPR doesnt help with that. I cannot send Facebook a request for my shadow profile, nor demand they delete all such data, as I have no way to ‘identify myself’ to them unless I have a Facebook account.
It's the path currently explored in a class action against facebook for forced consent and we'll see what happens.
So closing the offices wouldn't help.
Yes, they are based in Ireland.
I suggest using the identifier you received at birth to make the request plus your e-mail.