> What really makes me think though is the way China is being uncooperative
This reminds me exactly of the same kind of arguments made about Saddam Hussein when it came to WMDs before 2003.
It turned out that Hussein was playing to the domestic audience, not the USA. It made sense to him to stand up to the weapons inspections for domestic political consumption. Everyone in the USA, including the CIA thought he MUST have been actually hiding something, but he wasn't, it was all just bluster.
Similarly here, its likely all for domestic consumption. They just don't want to admit it came from China, period. They've been pushing the idea that it was spreading like wildfire in Italy in Sept/Oct 2019 (via some scientific article that never should have been published). They're happy to make the argument entirely about the lab leak theory because then they can rely on the scientific community to debunk that -- and then all that remains for domestic consumption is their ideas that it came to China in imported food.
And here's the kicker which is that if this doesn't make sense to you, it doesn't have to. They don't give one sloppy fuck about what you think. They care about what 1.4 billion Chinese people think. If you're convinced it is a lab leak they just don't care and that works fine for them. They can debunk that internally and push the idea that China is the victim.
And the zoontic theory doesn't help them as much, then they have to explain why it happened again after SARS-1 in 2003, and they might have to actually do something about a lot of the animal farming practices in China, and could lose face for domestic political consumption. Bunker mentality is better for authoritarian regimes than self-reflection about mistakes.
(See also Jose Mourinho's player management style)