Honestly, I don't fully. From a standpoint of a lab accident, evidence of natural zoonosis near Wuhan would be exculpatory and they'd have no reason to conceal it. But the CCP also seems to be pushing to exclude any origin whatsoever within China, like with their frozen food theory (which is thoroughly rejected by almost all scientists physically outside China, but which the WHO team nonetheless seems to be considering).
So I think it's entirely possible e.g. that China has confidently determined the non-lab origin of SARS-CoV-2, but that it's from an agricultural practice so reckless that they've decided it's better for their reputation to leave everything shrouded in doubt. It's much more obvious to me that China is concealing something than what they're concealing. (Of course, that's usually how concealing stuff works.)
That said, I still think zoonosis near Wuhan is unlikely. In a pre-pandemic publication with no incentive to lie, the WIV studied antibodies to SARS-like viruses in the blood of people living near bats in Yunnan province. They used blood from people living in Wuhan as a negative control:
> As a control, we also collected 240 serum samples from random blood donors in 2015 in Wuhan, Hubei Province more than 1000 km away from Jinning (Fig. 1A) and where inhabitants have a much lower likelihood of contact with bats due to its urban setting.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6178078/
So while it's possible that natural zoonosis did occur in Wuhan, I believe that would require the WIV staff to be genuinely mistaken.