Well CW was alive on previous DB becouse there were a lots of fights between players. And ppl killed everyone on battle maps, sometimes even on normal maps. That's when CW was used, when ppl went to sleep or to work and noone was able to look after party. Now noone kills anyone. There are no raids on battle maps. Noone will lose exp to stay and hunt for fenrir instead stay on vulcanus/relic/swamp.
Maybe with better mats drop it would be alive, but again fenrir is end game item, it shouldn't be easy. I don't know how many ppl would go to CW just to drop fenrir mats, probably ppl would just put alts there.