Oh that's easy: an authoritarian state would be arresting irrespective of the origin. They want to control the message , no matter what. The truth is a distraction in that case.
Once things flip, and the public becomes aware, then they can re-write history and make them national hero's. Chinese citizens are apparently skeptical of their own government, and get pissed off a lot, I suggest the Doctor who made the discovery is a little bit of a populist hero already.
The CCP's actions demonstrate they are fully authoritarian, that's about it.