Of course Ziyun can't walk fast with these injured people. She can't leave them behind, or they will be wiped out by the Devil's Gate.
Ziyun took them to a safe place where they are now living. When she saw that the Devil's Gate was not catching up with them, she let them rest here first and then send letters by themselves, which would be faster.
Ziyun now gathers these people together, ready to go back with Ouyang Yu to kill a rifle and revenge those who died.
When Ouyang Yu saw the tired faces of these people, he knew that they had traveled a lot and suffered a lot...