Then it's not hard to understand. As the saying goes, Shaolin Kung Fu is the best in the world, and it represents the highest level of martial arts in the Central Plains, and this representative of the highest level can't even hold a Khitan with dozens of masters. If this thing comes out, wouldn't it be a joke? So they can't give up Xuan Ci.
Secondly, these guys killed Xiao Yuanshan because of an anecdote that turned out to be false. As the head of the first faction in the Central Plains, he made such a reckless move before he figured it out. I'm really sorry about his title.
Third, after jumping off the cliff, they learned that the man's surname was Xiao through a suicide note, and Xiao had considerable influence in Qidan. Small and distant mountains can beat them out of the water. If the Xiao family is out of the water, it will take minutes to destroy Shaolin. Once Shaolin is destroyed, the Wulin in the Central Plains will be born to die, so they can't reveal Xuan Ci's true identity.