The video states that dialysis doesn't perform all the tasks of a healthy kidney. If that's the case, then wouldn't a better dialysis machine be a more logical first step? That removes the size issue from equation.
The tubes also need to be frequently opened and used for self/manual dialysis that may be needed on a regular every-7-hours kind of way.
A friend of mine had his kidneys fail and he was on manual dialysis every 7 hours or something, every day, and could never miss ine. Once due to a power cut he had to drive 3 hours to get to a working microwave because he had to heat the fluid bags to body temp before using them.