If the lab leak was real, covering it up to the extent they did requires a literal conspiracy (not to mention hypothetical function gain research). In the absence of concrete evidence, it is quite literally a conspiracy theory.
You mean the literal proposal to put furin cleavage sites on coronavirus collected in the wild, filed for a grant in 2018, which was rejected for being too dangerous. Also, SARS-Cov-2 is the only beta coronavirus with a furin cleavage site. And if you have ever been anywhere near academic grant process, you'll know that you use a previous grant to do the next grant work, as preliminary results.
So tell me it is just a coincidence that just after writing this grant proposal in 2018 to take coronavirus in the wild and putting furin cleavage sites on them, the first beta coronavirus with a furin cleavage site turns up in the same place right next to the lab, right after they moved their sister BSL-2 lab.
https://virological.org/t/tackling-rumors-of-a-suspicious-or...
I believe what you're describing is rather "the coordinated malevolent animal transmission theory".
Cover-up is the default mode of handling failure in an aspiring Communist state. When a major accident happens that can be covered up, it will be covered up.
The above mentioned Sverdlovsk outbreak was presented as natural as well: the official culprit was cough a wet market nearby cough. Took 13 years and the dissolution of USSR to admit the cover-up.