Unfortunately, SARS-CoV-2 is a very contagious virus, so it's hard to contain. A lot of ink has been spilled about the Wuhan BSL-4 lab, but these viruses were only considered to be a BSL-3 pathogen, and were handled in Baric's lab at UNC in their BSL-3. I would assume that they would also have been handled at the WIV's BSL-3. There had been reports of biocontainment lapses at the WIV, and there have been a number of lab escapes of various pathogens including SARS at other Chinese labs.