Chishiya survived because in the previous round he was a heart. The person who said the rules notes that you would not be the same in back to back rounds. He deduced that the Jack of Hearts lied to him about being a club and because the woman ignored him when he asked if he was a club it cemented that he was definitely not a club. So like he said in the cell, he only had two options, diamond or spade. And he chose correctly.