Board Thread:Naruto Discussions/@comment-5054236-20150717003436/@comment-6769189-20150717021722

Kabuto was never stated to transplant the cells into Sasuke, just that he used his research in them to heal Sasuke and the databook makes no mention of a transplant either. It said Hagoromo gave it to him, not hastened the process. Hagoromo is the only reason he has the Rinnegan.