I found this to be an extremely engaging read and compelling story.
TLDR; The likelihood of it being lab related is high. The likelihood of it being directly malicious low.
My Take form reading it: The lab in question needed to collect bats for research. A person who collected the bats did so with insufficient safety and is likely patient 0.
And this sounds like a reasonable possibility to be explored. Accidents happen. Lapses in procedures happen.
The problem is that early on, and still in some circles, lab related equates to malicious bio-weapon and/or China purposely attempting to destroy the world. It's important to separate the two, and hopefully this is a cautionary tale for all labs to review their policies and procedures.