Responses
It was more so to keep her quiet, if they left maomao at the palace she would have told someone about the clinics head lady instructing others how to make poison, thus revealing their plot much sooner making it impossible to carry out their original plan of escape/seizing of the imperial throne which is why they took her with them.
I still don’t really understand the goal of kidnapping Maomao. Wasn’t it clearly a loss on the Shi clan side??