Maybe you really did do a good job. A few students complaining means nothing. I have been teaching in China for several years and this stupid "student evaluating teacher" nonsense needs to be stopped. Chinese students in general are not very smart, they do not know what is good for them. Their parents are even less intelligent.

Maybe you were labelled as a bad teacher because you did not play any "games" with the students. If the other teacher was playing childish and absurd games with the students then the students probably liked him.

Welcome to the China's education "entertainment' industry. No wonder there are no first class universities and colleges in China!