The best theory I’ve ever read, wrote about miners working in caves with bat who came down with serious pneumonia, or something like that, in the area that the lab sampled viruses from.

The viruses could evolve quite a lot in an immunocompromised individual.

The virus was then probably leaked as part of the work to sequence its genome. So they wouldn’t have published anything on it yet.

I don’t think they did any GoF research or engineered the virus in any way.

I’m fairly certain China knows a lot more about what actually happened though.