I personally think Obitos fused with both Madara and Zetsu. The Ex Edo Madara dosen't seemingly know a lot about Zetsu, he hasn't called or tried to interact with him once, dosen't seem to even know of Sasuke, Itachi either, just some Super Power thats been asleep since before Nagato had the Rinnengan with J-Man training them.
Hit me tha right way, I gots no problem reppin' ya, and look for nothing in return. Just letting Ya know
You have dishonored my Family, and a Shaolin Temple...
許 Yurusenai 許