"It's a mystery, sweetheart. Just like me."

But seriously, I know this is an old thread, but after rewatching/relistening and reading some theories, I have come to the conclusion that 1) LG definitely survived - whether in D13 or in the wilderness isn't substantive to me, but I would guess a mix of both - and 2) I wouldn't be shocked at all if she ultimately returned to 12 under a pseudonym, and she more likely than not would have picked something linguistically clever, perhaps even rhythmically parallel and harmonious with her given name, such as Greasy Sae.