Fundamentally, you are not going to find any direct evidence that the virus came from a lab unless the virus has signs of being engineered (which seems to not be the case).

Only in the last week or so major news organizations have started covering the theory of lab escape of an unmodified pathogen. You can find tons or articles arguing either way.

Given the fact that almost every city in China is going to have wet markets, but Wuhan is one of the few (only?) cities to have labs researching these types of viruses it would be irresponsible to not consider the possibility. Given that the CCP is going to do the utmost to cover up any negative stories you are never going to find any smoking gun level evidence.