Yang Le saw Kai Le for a long time, however, the young prince in front of him did look innocent even though he was actually quite smart, just lacking in experience. Being one of the Emperor's confidants could make Kai Le one of the suspects too, he couldn't trust his cousin completely.
"I don't know how my order plaque got there, every month guard Song will give plaques to every guard in charge of carrying my name to every corner of the country. Some volunteer at the border, join the imperial infantry, and eventually, some of the plaques might disappear. We can't control something like that from happening, if you want to investigate I need to know the name of the guard who carrying this plaque. His name and rank will ease the search. I guess, the Imperial Investigation Division should have done it first, right? You guys are a special division trained by the country, things like this shouldn't come to the surface if you really investigate it further"