Huh? Rinnegan was originally Madara's, that is true. However, Madara passed on the ownership to Nagato and Obito took it from a deceased Nagato. Therefore the Rinnegan is also his as well as Nagato and Madara's. The Mangekyo Sharingan - Madara in no way, shape or form helped Obito acquire. He did it himself by seeing Rin die in front of him. The Zetsu Body and the Hashirama DNA was essentially a gift. If I buy you something for Christmas or your birthday, it is now yours. I may have made it or bought it but I gave it to you so it's yours, not mine. Same case applies to Obito.
Obito would defeat Edo Madara High-Diff. Obito has the Edo Jinchuriki and Kamui as well as the Rinnegan Techniques and Mokuton. Madara has Susano'o and the Rinnegan as well as Mokuton. I will restrict Gedo Mazo as both can summon and use it and that wouldn't make much sense. Madara knowing Obito would instantly go all out despite his habits of slowly making his way up to stronger techniques. Susano'o' will be his first step and fight Obito who will barrage the fellow with Bijudama. He will occasionally brawl Madara out with Mokuton etc. However the battle will be long and destructive and will simply end with Obito using Kamui on Madara.
Madara has no known counter to the jutsu and will essentially be stuck in the dimension forever. Obito can send an Edo Jinchiriki there and blow him up as well. Obito wins with high diff. and not all if any were given to him by Madara. Madara passed ownership so it is no longer his.