I already started writing the post and he does know it’s the Sound.
He hesitates though. Actually I think he just freezes since he doesn’t know what to do. On one hand, he has the same mentality he had with the Mist, believing Hina would kill him if he went over there. On the other hand, deep down, he knows the freedom Orochimaru is offering him isn’t what he wants. But if he betrays the Sound, then he has no place to go. So he might see it as a lose/lose scenario.
I feel sad for Kiro too since I see him as being lost and alone. That’s my bias seeping out though lel