What is the name of this?

[Money pit]

Yes they do look like bleached BTAs . With very little zooxanthellae, they wont be able to get much food from the lights, what seems like growth is them reaching up and expanding to catch as much light as they can. If you can offer them a bit of food each day, they may start to recover. But just a tiny bit to begin with, until you know they are eating it. Often they will take the food but later spit it out when the lights are out, you don't want to feed a lot incase it fouls the tank. Mixed sea food is best, if you can puree it in a blender so its like a paste, it will be easier for them to digest leaving more energy for recovery. If you cant blend it, chop it up as fine as you can. BTA's will often split when they're stressed , it a survival tactic where one may die, but maybe the other will live. Keep your fingers crossed and may be you will end up with a few nice BTAs.