RNG means random number generator so it means its random not actually a item you need. and the forgotten cave and wasteland are unlocked by exploring the cave system you get after doing the meeting between korg and everett. if you didnt take korg home with you i dont know if this is possible to unlock.
(also the clash with barrel thing is supposed to just happen randomly after you entering the bar whenever, you prolly need the werewolf story done and logan at one heart for it though)