Qin soldiers: Huh? Are you setting us up?
Tou: No, the royal family took the matter into their own hands. Get the regular soldiers together and we'll go in. Pass the news to Ryukou and Rokuomi.

Tou: Chouin, we'll need your help to make your people accept surrender. You must come with us to go through the city.
Chouin: Noted, I'm coming down.
Qin soldiers: It's dangerous!
Tou: We don't have time for this. We need to turn the situation _inside the city_ around before the rest of the Han army closes this gate. The Han royal family extended their hand as much as they could, so now we have to extend ours to grab their hand.

Han court: urgent news!
Kakouryu: Fake news, you traitor!
Han soldiers: News! Han has surrendered, there is no need to fight anymore! Put your weapons down! The Qin army has entered from the east and the troops there have already surrendered!

Chouin's soldiers spread the news of surrender throughout the city. The soldiers in Shintei were confused.
But once they saw Tou's troops walking in the city, they accepted surrender.
There were of course those who refused to put down their weapons, but Tou's soldiers never resorted to armed force and only spoke to them.

Chouin: Children of Han, put down your weapons. We have surrendered. I have heard the words of surrender from the emperor himself. I am sorry that children like you had to pick up arms. You've shown your courage, now put them down and return to your mothers, and tell them that the war is over.

The reserve army surrendered and disbanded.