Chang Yulong and the others were right. Zhao Hai was indeed looking for people to find out about the matter of the surrender and who had put in the most effort. As a superior, you could turn a blind eye to the little tricks of your subordinates, but you couldn't really not know. If you really didn't know, then you, as a superior, were not qualified to be a superior.
Zhao Hai also knew that if Chang Yulong was really smart, he would not have made any false moves in this matter. However, he was still very careful because some people would always like to take risks. They always thought that they were very smart and could hide from everyone. However, they didn't know that what they did had long been seen by others. There were many idiots who looked smart in any world.
One must always be on guard against others. Other than his own slaves, Zhao Hai was suspicious of everyone else. He would rather blame the wrong people and be more careful than to be deceived by them.