I think eyes 47 is right your dad can live longer he just needs to eat well and be on dialysis. I will be on dialysis soon maybe this Monday. I am in the 4 stage of kidney failure on both kidneys I'm 43 years old.
Dialysis would be needed then. 3x or 2x a week. depending on his labs.
Basing on his age, 5 years of life expectancy would be spectacular.
If he was, say, 20-55 years of age, a life expectancy of 15-20 years on dialysis can be expected.
all the best.