Try logically. Something that changes sprayTypes like liquid lime, herbicide fertilizer combo (I have no idea how the mod it is called, but makes possible to have herbicide and fertilizer toghether)...
So, I tried a new save with only Precision Farming and still couldn't kill weeds with herbicide.
ChatGPT says the map is explicitly overriding the game’s spray type list with its own file, and that file only defines COMPOST and ANHYDROUS—there’s no HERBICIDE entry at all.
