Whenever we see someone have a Purple Rinnegan, we automatically assume they can use all the Six Paths even though there's no evidence for it. I hereby invoke that ancient rule and say that Momoshiki, in his Purple Rinnegan form, can do that.
Secondly, Susanoo is still Ninjutsu and therefore, by the known rules, can be absorbed and replicated by Momoshiki.
So, yes, assuming Madara has perfect knowledge of Momoshiki, he'll not take the risk and will engage in CQC combat. Any ninjutsu used by Madara will be absorbed. Kurama in this fight is just ammo for Momoshiki to take. The physical prowess of Kurama is not enough. By what we've seen of the Rinnegan, Momoshiki will just take control of Kurama, then absorb him and use him as ammo.
During Taijutsu Momoshiki can move in, paralyze Madara and take his chakra in a single easy move. Madara doesn't have Six Paths power and can't stop it.
The less they know of each other the more it will move in Momoshiki's favor. Even with perfect knowledge Momoshiki's Six Paths power is too much for Madara to deal with. Byakugan leaves no openings. Rinnegan leaves no move unseen. Absorbtion makes ninjutsu useless. Taijutsu-wise Momo sparred with two extremely powerful ninja. Genjutsu is useless.