I think BZ is absorbing madara

[Draw]

If this is the case, madara(who has kaguya inside of him), will be within BZ who is attached to Obito, black zetsu will completely take over Obito's body and Obito's body will actually be the vessel for kaguya, and then at a certain point obito is going to regain control and either warp himself away, or he will respond to the sage's tools and get sealed inside the pot. Can't see the sages tools working in any other manner, nobody is just going to answer the sealing pot if they know what it does (Kaguya)

 

[HashiraMadara]

good to know what you're thinking!