I asked in a ticket and got this reply.
Okay, the Character Clone service has been retired. All clones that were not activated before July 26, 2022 were deleted. Customer Service cannot restore deleted clones or transfer active clones to different game versions.
If you had a WoW Classic character and you never chose to activate it in either WoW Classic or Burning Crusade Classic, then the Burning Crusade Classic (now Wrath of the Lich King Classic) version of your character has automatically been activated and will be available for play.
Names can be used again once the Clone has been deleted.
Sounds exactly like the stuff I said. Sorry guys, it’s over, the last part confirms it.