Deliver it to Uffe, the werewolf leader who gave you the quest. Do note that there are a lot of bugs with that amulet, so don't mess around with the pillars a second time (You can get a second amulet, but you won't be able to finish the quest) nor should you be wearing it when you give it to Uffe (He took it from me and I retained the health debuf, possibly not permanent but I reloaded almost instantly).
Edit: Also make sure you cleared out all the weeds in the cave with the pillars. Uffe won't accept the amulet until you've cleaned the place. You do need to solve the puzzle with the barrels on the bottom left of the cave to access the room on the right to get to the last of the weeds. Also, it may be possible to get a second amulet after finishing the quest, I haven't tested it.
As for the new CG I think that's in version 0.0.17, the Patreon version. I only have 0.0.16, the public version, so I can't help you there. If you're on the public version then there shouldn't be any CG's that require an ally to unlock. Unless I've completely missed something, the last two that are available in the public version are the "Losing to the bandit boss" CG and "Captured by bandits" CG.