I think this part in bold I get. Where I get confused was how ridding the the first of the light wardens would also stop black rose, which is directly tied to the 8th calamity. Could it be that their fates are tied? If so it makes it all the more interesting that while we took care of the first, Zenos also single handedly and coincidentally eliminated the black rose threat on the source. Leaving Elidibus had to retreat to rethink his strategy entirely. However, I still haven't done any 5.1 content, so that is the impression I was left with.