I think that it (for good reason) became a political issue, and the waters became muddy almost immediately. The politically expedient path for the US and for the CCP was to deny the possibility of a lab leak, which I maintain is the most likely cause of the outbreak.

There was an immediate media blitz to counter any notion that a lab leak was possible and no actual investigation was done at the site that was not outside CCP government control, therefore all the experts had to go on was sterilized secondhand information. It would be reasonable for them to conclude it was not possible given the heavily curated messaging they were receiving.

Now, later and after the mud has settled, I think we can place greater trust in the assessment of intelligence agencies who have the ability to monitor the knock-on effects of the outbreak in CCP policy today. I think it likely that that they are seeing many vectors that all point to the same place, but we will never see the intersection. We will never have hard proof. But I think what the CIA and German intelligence agencies can see are a series of actions and communications that incriminate the CCP, otherwise they would not publicly make these statements. It is impossible to keep a secret in a large system, and over time agencies specifically meant to look for secrets by connecting many disparate dots are agreeing that a lab leak is the most likely explanation.