since when did orochimaru kno about minato being sealed in the reaper. he had no knowledge of the jutsu in its entirety. he had the fourths dna and he tried to summon it not knowing it was sealed.If Orochimaru would've tried to revive Minato knowing he was in death God, I see no reason why Kabuto wouldn't try a similar feat knowing Shisui em has no eyes. When nothing is missing they can be revived with all there techniques. Izuna eyes were missin no way for him to be revived with all of his original techniques, and Kishi seems to only made Madara a special edo no one else. Everything suggest he gave him the Rinnegan somehow since he didn't have it in his prime, and how can Kabuto make his body younger? Why didn't he make Nagato walk again?