I don't think Kris attacks Susie and Ralsei when you win the Knight fight. Now, don't get me wrong, they're obviously cooperating, but the "heart gets dragged away" animation isn't as important as people thought. You regain control and can menu around again right away. Kris will even take a swing at her just as before. We still don't know what SWOON is, but the idea that he's been sitting on that same power and sandbagging every other encounter he's ever had is just silly.

Ralsei turning and looking to say "how c-could you..." is him looking at SUSIE; he lines up directly with her face as she's lying on the ground. So what's the implication? I dunno. How could you lose? How could you keep up in the first place? I dunno. But the idea that he'd witness Kris OHKO Susie and then never even mention it again in any later dialogue branch, that just seems silly.