China could straight-up admit the most mainstream "supported" blacklisted theory, and would look like a fucking saint.

"A virus came from a lab in Wuhan, being funded by that Fao Xi fellow from the Americans. He wanted to weaponize a virus we did not have, so we took one from a Canada lab that had no security or oversight. He assured us it was all safe, and so we followed his guidelines. As his researchers worked on this gain of function research in our lands, it got out, thankfully mid-research and not at a truly lethal weaponized point. Upon realizing his lab was not what he promised it would be in terms of safety, we burned it, flooded it, then sealed it in concrete."

They could absolve themselves of nearly all responsibility, really.