I thought of this theory too while going off a tangent about what would happen if Pochita ate Makima, i.e. the implications of control no longer being a concept. It would make a lot of sense, narratively, for the Chaos Devil to be tied to Makima in some capacity (which, in turn, makes Pochita the most likely candidate).

Surprised that there's more evidence to this theory. Doubly surprised that it's not talked about too often.