You’re absolutely correct about functionality! For the price, you’ve already gone above and beyond, imo.
So I have it working, sort of. I store an array of enemies killed in the player controller, only when NPCDefeated is called (add unique to the EnemyKilled array), then when ever you interact with a quest giver it calls RecheckDefeated, which again calls the NPCDefeated function and passes in each ID from the EnemyKilled array. I haven’t thoroughly tested it against other Enemy NPC and other quest givers to ensure there isn’t any mix up, but with only one enemy and one kill quest giver it works. I’m not sure how scalable it is though so I would imagine I would need to clear out that entry into the array after the entire quest is completed.
Similarly though, if I already pick up the bandit sword, Bob doesn’t know I have it, so will need to build out the inventory check function.