I don’t think we’ll ever find out, for two big reasons. One, it happened so long ago now that unless some sort of incontrovertible contemporary evidence is released there will always be uncertainty. Two, there are so many powerful interests at play with regards to funding gain of function and bioweapons research that admitting in one way or another that Covid-19 was made in a lab would have the potential to end that kind of research.

One interesting thing I recently read (aside from the bits Jeffrey Sachs is talking about) is that a whole bunch of US states could have tested waste water samples for the virus, samples taken just before Covid-19 officially came to the US. Only two states have done so, and it was even implied (IIRC) that some samples have been destroyed. Sachs also mentioned in at least one interview that in the US NIH supported labs like in Wuhan, there’s basically no PPE required for working on samples of corona viruses, even very contagious ones like Covid-19.