There are several regulators of the pH in the human body with the kidneys being the most effective regulator, and the only times they fail do their job is when a person overeats a combination of yeast-feeding foods which produces an overgrowth of yeast at which time the intestines start to become too alkaline far beyond the attempts of the regulators. The other way is when a couple has unprotected sex several times within a 24 hour period. Since semen is alkaline and the vagina is acidic, this can produce an alkaline environment in the vagina, and if other factors are present, this can cause either a yeast infection or even a Candida overgrowth.
I suppose the fact that the body can self-regulate its pH balance says a lot as far as your theory.
My advice would be to stick with the diet and continue as you were. If you’re truly sticking to the diet and not feeding the Candida they’re bound to be dying.