I am a virologist, and I recognize there are multiple examples of emerging diseases that jumped species to infect humans. Viruses like HIV, MERS, SARS, Ebola, etc. Therefore I don't see any reason to think that the covid-19 virus did not jump from bats or some intermediate species to humans, given that other SARS viruses have done just that. We have not found the exact covid-19 virus in any other species, but they certainly carry highly related viruses.Are you still going with the bat to human connection?
There is no non-circumstantial evidence for your preferred explanation, that this was a lab produced variant.