Мафия 58. Earth Tone

The winner overlooked one thing. Kosha and Nephal were not just switched; there was another clue: a potion that Kosha drank before going to sleep.

Are there any doubts here? In my opinion, no one but the witch could have been behind it. Well, it just so happened that the switch occurred at the same time, and this assumption connects two clues in one sentence. Hmm... I thought she was dead.