C3299 The King of Divine Beasts
Originally, the Primal Chaotic Black Flame could have let it go, but the Primal Chaotic Black Flame had also come out of the God Realm. He naturally knew that the Devil Dog had placed a God Realm mark on his body, which was specially used to deal with the beasts.
So the Primal Chaotic Black Flame knew that they were not the ones who passed the test to escape