If it was a bioweapon, then it is logical to think that a vaccine would have been created along with the bioweapon.
So if the Chinese magically produce a vaccine six months before the most optimistic estimates for finding one, I think that would lend some credence to the bioweapon hypothesis.
I would assess Covid-19 as an early-stage research experiment that escaped from the lab, rather than a finished bioweapon.
Add in some bureaucratic infighting, high-stakes finger-pointing, self-deception, and then panic, and here we are today. With all the propaganda and incentives for deception, the Chinese can no longer determine what is loose in their country.
The Chinese do not have a vaccine, nor do they have effective cures. Nor will they develop any. It will be up to Western nations to clean up this mess.