well one thing that is for sure that masked madara is one from konoha and he is not Uchiha Madara he is a filler guy and he knows everything about konoha but there is one thing that is confusing......Why until the very end itachi said that he is madara while acc to most of the suggestions and the modern look of manga it completely negates his suggestion
It seems that the masked man has had a non-black robe on this entire time, and i wouldn't be surprised if kishi threw in some kind of crap to explain how the masked man has been madara this whole time.