The only recent evidence it contains is the fact that 3 researchers from WIV sought hospital care back in autumn of 2019 with symptoms similar to COVID. However, this piece of evidence is hardly consequential without further details:
- First, most common symptoms of COVID are indistinguishable from common cold. If the researchers were known to have any "signature" symptoms like loss of smell the article would certainly mention it.
- Second and more importantly, China doesn't have a robust GP/family doctor system found in western countries. As a result, many people would go to hospitals directly whenever they're mildly sick.
Taking the evidence as we know it now, the straightforward explanation is that 3 researchers caught cold, got mildly sick, so went to the hospital to get prescriptions or doctor's notes for sick leave (in China it's common for employers to require a doctor's note even for a short sick leave).
That said, I believe the lab leak theory is still plausible, and shouldn't be ruled out unless a clear transmission path from bat to human has been identified (which was done for the 2002 SARS outbreak). But I also think that we may never know. I trust that some theories put forward were in good faith, but so far they are little more than speculations.