Greetings im a bit late,but i was playing here long time ago on the Neltharion,had BIS charachter and some paid items etc,and since cataclysm realm got removed i never had any refund for that or similar stuff.After neltharion started being lower populated i left the WoW.
And now I would like to start playing WoW again.
players had a the chance to copy their Cata character to Wotlk (it would lose all gear) and to MoP (it would keep everything )
It is too late now. As last chance you may try to contact support team by sending an email to [email protected] (or by opening a ticket in-game if premium account)