They had tried to act like a stream Kiara did last year with one of the alleged NijiEN clique members was somehow new so they could try and drag HoloEN down with the sinking Nijisanji ship. So I guess the logic was "Clique + Kiara, and Kiara + Mumei, therefore Mumei + Clique".
Nevermind that the stream was way before the winter Niji yabs. Or that the entire clique narrative is (currently) a /vt/ original fiction.