This is what I've heard from a friend who does business in China and visit China often. Apparently the locals believe that some of the WIV lab animals were sold to the wet market and the rest is history. It's a hearsay. So use your own judgement.
It saddens me to say how much racism and xenophobia Asian people still have to endure because of some conspiracy theories. The way we've been treating Asian people will be the biggest human rights violation in 21st century.