At first I was really disappointed in Dowun for agreeing to leave Jayang alive, even under the condition that she would be sent far away. But when I looked back through, I noticed the author's detail to body language and am blown away. The moment before that Dowun lays down the hardest question, "Is Jayang still gone," he steeples his hands. It's a signal of power and confidence. (To put it in perspective, a friend of mine once got chided by a professor for "arrogance" after she steepled her hands during a critique of her writing.) In the next panel showing his father's face, he moves a hand up to pick briefly at his face. Attacking self like this is a common signal of uncomfortableness and dislike of something. He then leaves his hand up for the rest of the conversation about Jayang. Any barrier in a situation like this between a person is a sign of defense or wanting to be far away.
I'm not sure I trust this author enough to read too much into it, but I hope it was all intentionally written in. It gives me hope that Dowun is about to reign his family in. If nothing else, he seems confident that he's superior to his own father. On the other hand, the fallout with Hong Lyon might be pretty brutal if he confesses that they kept Jayang alive.