As for the reason..
There was no reason!
If one was to insist on a reason, the first reaction of the Night Guardian was that "Xu Xiaoshou" was the reason.
The Chief of the Transformation Division had died in a battle, in the Yunlun mountain range. Saint servant, Xu Xiaoshou, was suspected to be involved and played an important role.
The red-clothed had kept this information from the lower levels of the division, but the smart ones in the upper levels could think of such information without even asking.
Not only did Night Guardian think of it, but his idea had also been confirmed by Sword Deity Rao.
After all, he was the person in the red-clothed who was most familiar with Saint Servant, Xu Xiaoshou. Rao Yaoyao did not avoid his question. She only wanted him to agree not to divulge the information after understanding it.
Zhu Mi'er appeared to be trembling in fear in front of her senior. She replied solemnly,
"I'm sure!"