Who Is Not an Undercover Agent?

I, Song Xiaoshi, have been undercover for seven years, The target is the Qingyun Sect's treasure. But what I don't know is that besides me, there are second, third, fourth and fifth spies in this sect. I didn't know that the elder was fake, I didn't know that the sect leader was acting, and I didn't know that the gatekeeper had a sealing token from three hundred years ago. I didn't even know that the real treasure was no longer in the attic. It was placed at the gate of the mountain and served as a stepping stone for three hundred years. Every disciple stepped on it when entering or leaving the gate. The person who stole it was the most inconspicuous handyman in the sect - a middleman who resold second-hand goods. This is probably the most outrageous sect I have ever seen - no one is one of their own. Including the guy who finished writing the story in the teahouse.