Knowing Kim dan it's definitely GUILT
I see it as failed love. I think he loves him and feels he can never live up to being good enough for him. He hurt the man he fell in love with and ruined his spotless record so he can’t face him now. Fear and guilt play into it but it’s a broken heart.
Imo I believe it’s a mix of guilt and fear. In the panel where Dan remembered the spray incident, his expression to me looked like he was extremely anxious/scared. I also think that the fallout from that incident left Dan with trauma, cause when Potato brought up the spray incident last chapter, Dan flinched then too. And since he’s a meek softie, having a gorilla like Jaekyung yelling in your face about to punch your lights out would terrify anyone to their core.
In short, Dan is probably scared of being around Jaekyung now and has no trust in him.
And plus, if Dan went back to Seoul to work for Jae, he wouldn’t be able to be around his grandma in her final moments, and since she’s all that he has, he doesn’t want to be apart from her when she eventually passes away.
You're all right. Though I'll go even further.
Considering his desperate situation, I think he's fed up with everything and going back with someone like Jjk is the last thing he needs right now. It's a mental and physical exhaustion he's showing; he looks broken to me. If not for Jjk being almost magically there he'd have drown himself for good by now. It's not a surprise for him to feeling like this considering his sad past, his encountering with the mma guy that only worsened his already lack of self-esteem, his job that he's about to lose... his only remaining family that's about to leave him also... That's too much for one person, particularly for someone who tends to blame everything on himself like Dan. If he has a more carefree nature he wouldn't suffer this much, I believe.
You don't spend sleepless nights like this drinking, you're not sleep walking into the ocean like that without grave reasons either, I think he's deeply depressive and isn't fully conscious of the state he's in.
So of course when he has such materialistic solution coming from the very person who made him suffer, he'd refuse. Jjk needs to see further than the first impressions and show empathy towards Dan, things he's not accustomed to show.
While it’s nice to see Dan finally putting his foot down against Jaekyung, I’m curious about his motivation as to why. Is it really because he’s had enough of Jaekyung’s mistreatment, or because he still feels so overwhelmingly guilty about what happened (though it wasn’t his fault) that he feels he has to refuse out of obligation/so he doesn’t “burden” Jaekyung anymore?
I think it’s interesting how the last few panels when he says he’s not taking money from Jaekyung anymore, neither we nor Jaekyung can see Dan’s facial expression anymore, he’s turned away. Again, is it detest for Jaekyung? Fear? Guilt?