Eh, ofc it will take a while and resources but in the end they could use it for enemy NPCs too or recycle it. 
Ooooor take the lazy route and don’t add the leg part of the armor, only boots and the upper body.
Night Elves try Diplomacy on their cursed brothers and sisters if they want something from them. Could add a bit of a struggle inside the faction, good for the story I think(and them probably making more unfit decisions in the eyes of the Night Elves but they get their job done, maybe in the future even get a strong bond with their uncorrupted brothers and sisters).