This is obvious. CIA is the spy agency. Given that China was stonewalling any attempts to learn about what was going on in WIH, it seems natural for the spies

This is obvious. CIA is the spy agency. Given that China was stonewalling any attempts to learn about what was going on in WIH, it seems natural for the spies to see what they can learn. They likely have access to many internal Chinese communications. Also obviously, this isn’t an investigation on just “anything”. This is about the origin of a global pandemic with millions of lives lost and billions-if-not-trillions of dollars of economic impact. And BTW again your biases show through with your use of the word “cursory”. On what basis do you conclude that the CIA investigation was cursory (or the DoE investigation, etc)? We don’t have access to those reports.