In fact, the military weapons were indeed hidden in the coffins of the Mulan people and transported out of the city.
Including the burial site chosen by the Mulan people and the Feng Shui Master favored by Mulan Old Arutai, all were selected by Chen Jie.
It was all to accomplish this scheme.
The scheme began with Chen Jie leaving the city, drawing the attention of all eyes, and then hiding the military weapons in the coffins of the Mulan people to be transported out of the city. Once they reached the destination outside the city, those Mulan people, who don't practice the Han burial rites, simply delivered the coffins, dug a pit, and began to bury.
They didn't even finish burying before the Mulan people hurried off, impatient to leave. After all, they were neighbors, and Tara's direct relatives had all died out.
So, it wasn't taken seriously by anyone.