Who planned the plot to assassinate Emperor Ruyi in the palace?

Jin Yuyan and her fourth brother Yong Xuan conspired to design the assassination of Ganlong in Mulan paddock. The purpose was to arrange assassins to assassinate by false means, and then let Yong Xuan save Ganlong during the assassination, make Yong Xuan show off, and let Jin Yuyan and her son regain favor.