I think the kidney did not sustain in Don's body, and it was his sister that donated it.
But, given all that, even if Don signed all of the waivers, why would you want to go and compete on stage? Just to show everyone or even yourself that you can be on stage competing in a pro show.
What if something happens? Anything? Would it be worth it.
Yes, just because the dialysis machine, even with revolutionary advancements, does not mean that other factors are taken into routine. Why even take a chance?
So later on say I competed one more time on stage...