First, understand who Daszak is: yes, he's definitely an expert, but he is also not a disinterested observer. He is the PI on grants from the NIH that funded Bat Coronavirus research in Shi Zhengli's lab at the WIV. He's also stated that he's friends with Shi Zhengli.

The sequence of the virus strongly resembles RaTG13-CoV, a bat coronavirus discovered by WIV. The sequence is almost identical, except for the spike protein. The spike protein strongly resembles a Pangolin CoV also discovered by the WIV. Shi Zhengli and another researcher from WIV are authors on a paper from 2015 where they transplanted the spike protein from one Coronavirus onto the remaining parts of SARS-CoV. They've also done "serial passage" experiments, where they infect either cell cultures or live animals, so that a virus becomes more adapted to that host. One of the animals that they used for these experiments were ferrets, for which SARS-CoV-2's spike shows extremely high affinity.

Now, it's possible that two viruses recombined naturally, but then why did the virus first show up in Wuhan? Wuhan is a thousand miles from the bat caves where they found these viruses in Yunnan. As far as we know, they did not exist in Wuhan, except in the WIV's freezer.