"Yunmeng Jiang has disowned him, Lanling Jin considers him a criminal, and Qinghe Nie has shown no interest in bringing him into their fold. You must convince him, Wangji - if he is ill, he will need the aid."

There is an underlying warning to his argument - if Wei Wuxian has not been accepted by Lan Clan prior to everything coming to a head, if there isn't some proof that he is returning to the fold, there will be very little any one person can do.