Man, Lili is the absolute best. She's changed so much, and I love the woman she's become. She's so grounded and just gets stuff done and sees things as they are and charges forward relentlessly, no matter what she's facing.
Aside from that, I think that rather than signaling a time rewind and alternate future path (I trust the mangaka to not pull that shit), this is about communication finally happening between Hak and Soowon. Soowon knew how Hak and Yona would feel about his betrayal, but he thought they'd never forgive him, that they'd hate everything about him, that they'd one day come for his life, but that didn't matter a) because he was going to die young anyway and b) as long as he managed to get Kouka back on its feet. While Hak probably doesn't forgive Soowon for killing King Il and betraying them, he's communicating that he has always known and had faith in how smart Soowon is. No, that's not enough to repair the bond between them, but it's important for Soowon to know that Hak still has a certain amount of unwavering faith in him, even if it's not the way we normally think of "having faith in someone" (believing in them to do the right thing, usually).