C90 Deliberately pretending to be deaf and dumb

So that day when Gu Xiaohua and Pan Wuneng were doing that thing in the carriage, when Gu Xiaohua wanted to report to Zheng General, Zywane stopped them.

What good would it do them to tell the Zheng General? Maybe the Zheng General already knew and pretended to be deaf and mute that it would be him who would suffer a loss after the report. Even if the Zheng General didn't know