Xiao Zhen reasonably suspected that Yan Qing did it for Ling Hua, and of course, it did not conflict with his revenge against Xiao Ze.
Ever since the imperial decree of marriage, how Ling Hua treated Yan Qing well was something he knew without having to delve into it deliberately—when Ling Hua liked someone, she would tend to their needs in every way, and he had already deeply experienced this over many years.
Because of that deep experience, he was suffocated and felt indignant inside. Why should Yan Qing do nothing, just have a pretty face, and upon being seen by Ling Hua, have her wholeheartedly like him, joyfully wanting to marry him?
If Yan Qing had continued to do nothing, Xiao Zhen might have thought that perhaps one day Ling Hua would cool off after facing cold treatment for so long and no longer like him. But now, Yan Qing had taken action.