Marble Dusting repair

[bradc]

Simple question guys - I had my gunite pool marble dusted last year in a deep blue. We had just bought a new house. There are cracks all over the place. Not leaking water, just highly visible cracking.
My installer "I have never had cracks before in 20+ years of doing this, will have to empty the pool and patch it up."
Questions :

1. Dumping salt water not good. We live on the top of a hill and my neighbor will have a salt refuge in his basement. Truck best way to do it? His house is 50 yards down a mild slope.

2. "Patching" I have read that when fixing a bad marble dust job it is a COMPLETE redo - no patching as colors will never match and it will look awkward. Do we agree?

Many thanks, I just want to approach this correctly with my installer - the dime is on him.

Thank you.