It's totally absurd to ok regular butter and forbid salted butter; salt does not in any way feed candida, quite the opposite in fact, and is perfectly ok, in reasonable quantity, in candida diets. Try to use organic Seasalt though.
Butter is the only dairy foods that does not give me allergies; the reason is I live in Europe and here, we have cultured butter, while sweet cream butter is sold in the United States and the UK.
In cultured butter, the allergenic Sugar lactose is turned into lactic acid thru fermentation.
So it may be that European style butter is ok, but not US butter. Hence the contradictions between candida different diets.