i thinkthat madara IS a jinjuriki but not by being forced to by accident....what if he was alive during the time of the SO6p and when the
SO6p sealed the 10 tails into the moon a amall portion of the ten tails chakra escaped and fled into tobis body.........then he would know the pain of a jinjurikki but knowing that the ten tails is more malevolent than the other tailed beasts what if instead of being able to shortly control it it was unleashed and ended up slaughtering all of tobis family and friends and what not......then he would know even greater pain then he somehow managed to gain control over himself........then since he is obviously smarter than oro he actually found a way to use the ten tails latent power to manifest off humanity or somethin like that..then somewhere along the line he met up with madara and they formed a plan.