There have been examples of bats excrement contaminating fruits on fields as a transmission chain. Accounting for these, often undiscovered, interactions is extremely difficult in terms of probability.
> we already know for certain the labs were transporting the bat viruses directly
In research from 5+ years ago, research which warned exactly about the fact how the virus already had overcome critical barriers to infect human cells [0]. A very plausible interpretation here can also be that said research was a warning about things to come, and is now mistaken as the original cause for it.
[0] https://www.nature.com/news/engineered-bat-virus-stirs-debat...