^ Yeah there is a bit of debate at the moment as to whether Madara is dead or if his consciousness is trapped within Kaguya. I hope it's the latter because it would mean that initially Kaguya was inside Madara when he absorbed the shinju but then after he got betrayed by black zetsu he ended up so far inside her that not only could he not get out but that his body became that of a woman. I hope the multiple entendre friendly outcome is the one that is revealed to be canon.
Also I dont think kishi is going to have Hagoromo send Madara into her dimension. He might be pissed off at black zetsu and Kaguya for betraying him as if they were in an episode of Game of Thrones but that alone isn't enough to suddenly make him a reliable ally. He's been corrupted for too damn long, not even Naruto or Hashirama could return him to the non asshole person he used to be.