Dethmold is doing a necromancy ceremony and I need to get some Gadwall in part II of the game. I heard that Master Myron is supposed to sell the formula but when I go and visit him he doesn't appear to have any formulas at all. Does anyone have any suggestions on another way to possibly get the formula or the potion and why Myron is not selling it?

I had the Full Combat Re-Balance mod on once but I removed well before I started Act II.