The spirit of this question is whether the King or his official spokespeople will give some credit to potions for his recovery from cancer. If they claim his cancer is cured outright and that it was done by "traditional decoctions" then that would still resolve Yes even though euphemisms were used. This question can be extended, but will resolve No if he dies from cancer-related issues, or if he recovers from cancer and gives credit to non-potion medicine instead.

https://www.dailystar.co.uk/news/latest-news/king-charles-doesnt-believe-chemo-32074683