Yeah, it would appear legalCanada has it on the nose. In adult plants gender is controlled by gibberellic acid and ethylene levels. If a female doesn't produce enough ethylene it will revert to producing male flowers. That's how colloidal silver, silver thiosulfate, and ga3 produce feminized pollen, by interrupting ethylene production. But this doesn't change gender or genetics, and no new genes are created in this process (i.e. the babies are not more likely to hermie than their mothers)
I would love to know how the sex determination tests work, tho. There's clearly some tell in the genetics. Phylos says they can even tell an S1 from the mother plant.