When I last had an everyday carry USB stick (5+ years ago) I found I never actually used it for anything.
I had Ventoy and some practical ISOs, and PortableApps with a bunch of useful software (firefox, foobar2000, GIMP, notepad++…) for when I was using someone else’s Windows PC.
…think I stored like two word documents on it, ever.
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.