Master cylinder help in Hawaii

If he did not bench bleed the MC properly and bleed the brake system properly,there will be air in the system.
True, but I am not sure how pumping the pedal multiple times would help if there was air in the system. It might help if the air was around the MC piston in some strange way like moving the bubbles around. For sure he should bleed the MC first, then the brake lines, whether he keeps his existing MC or gets another one.