Hello!
As most of you know, NPCs resetting are pretty obnoxious, and don't add any to the difficulty in the game, it just makes people lose time when they need to rush to a place.
So I suggest you implement a Vs. Seeker so that we could choose when to rebattle them and of course, keeping the 1-week cooldown for them, making the item fail if used close to npcs that were defeated before the cooldown ended.