> In 2015, an international team including two scientists from the Institute published successful research on whether a bat coronavirus could be made to infect HeLa. The team engineered a hybrid virus, combining a bat coronavirus with a SARS virus that had been adapted to grow in mice and mimic human disease. The hybrid virus was able to infect human cells.[11][12]
https://en.m.wikipedia.org/wiki/Wuhan_Institute_of_Virology
You make a good point. The wet market is only 20km from the lab, so if this one is lab-based (and not a bizarre coincidence) it seems much more likely to be an accident.