Dr Selye tested the results of stress over and over. Regardless of the stressor, the stages were the same.
The fact the some have low adrenal function their whole life has no impact on the fact that anyone who experiences enough stress will go through the stages.
And the fact that Dr Lam put his own spin on it for marketing reasons doesn't matter either. It does not negate that chronic stress causes one to go through these stage to eventual exhaustion.