I’m not so worried about Bluesky getting the huge wave of new accounts, but more if those accounts will be actively posting next week or just slink back to the dirty birdsite out of habit. Good to know from yours and other replies that its very active at the moment though!
All the CDLC for RS2014 work by pretending to be the DLC for “Smashing Pumpkins - Cherub Rock”, because it was given away for free as a preorder. If you get any of the other delisted DLC, you can use Rocksmith Custom Song Toolkit to change the ID to one you own (free or paid, as long as you have a steam license for it) and it should work.