Dumb

The fact that Sen-nu had gotten his hands on the video was quite surprising. Khan wasn't a high-profile figure in the dock, and Piran had even reassured him on that field. 

Moreover, Sen-nu didn't have the appearance or bearing of a leader. His behavior could be a pretense, but the alternative explanation that formed in Khan's mind made more sense. Factions among the Fuveall had probably stepped in to purchase the video and reach out to Khan.

Khan could understand all of that very well, but he remained confused. He didn't see any real value in his figure. Threatening him with something relatively valuable made no sense in his mind unless Sen-nu and the Fuveall wanted to use his connection to the Nele.

Of course, the realization that the Nele were the only possible explanation for that event made Khan's thoughts even colder, but he refrained from violent outbursts. He didn't want to jump to conclusions, and the situation was far from terrible.