Depends if he (Obito) has his paths. Because flying on the Nanabi and having it nuke from above would counter the pollen Madara produces with Kajukai Kōrin, as would staying close to the Rokubi's corrosive gases which can effortlessly disintegrate trees [
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]. The Sanbi and the Gobi could also destroy parts of this particular Mokuton construct via rolling and charging respectively.
I don't know. Maybe Madara outlasts him. Maybe Madara trolls him with a Moku Bunshin or two, although that's if Obito gets complacent and warps them into the wrong part of his pocket dimension. Or perhaps, Obito steals his soul with Ningendō. One is going to be hard-pressed to find a means of landing a critical blow. The other is going to have to pull out all the stops just to get through each wave of abilities.
I jus donno.