I understand what you're saying. However, Kimimaro was not only seen to regenerate his outer skin, he actually instantly regenerated his spinal cord, and the cells around it (if the cells around the Spinal Cord aren't regenerated death may ensue, and/or disability within the lower regions; legs, etc. I believe) it's also noted that the cells in which are located around the spine, and are destroyed via spine removal cannot be replaced meaning Kimimaro was capable of restoring his spinal structure perfectly (cells and all).
So I can say due to the canonically given event that Kimimaro can regenerate his cells.