No matter what, Qiao Nan was getting married and they had to let the Qiao family know about it, even if they informed only Qiao Dongliang alone.
Miao Jing had already learned from Zhai Hua that Qiao Dongliang had secretly handed the courtyard's property deed over to Qiao Nan. Qiao Nan herself did not even think that she needed that property. If so, it was even less possible for Miao Jing to be so shortsighted and shallow to get Qiao Nan to fight for ownership of the courtyard.
Fighting for it was one thing, while logic was another. Qiao Dongliang was rational enough to return to Qiao Nan what belonged to her. In comparison, Qiao Dongliang seemed much more reasonable than Ding Jiayi and Qiao Zijin.