Those scientists, and many others, are asking for a full investigation of the wuhan lab safety protocols.
Note that none of them are claiming that the virus was manufactured.
Origination of the virus has been narrowed to a leak from the lab and / or the market nearby. It’s also plausible it could have hit both at relatively the same time if the Bat trader sold some bats to the lab and then at the local market in the same time frame.
Origination is an important question in terms of traceability and understanding the pathogenesis of the virus.
It’s much more important that we (the broader scientific community) make sure that all known safety protocols were followed at WIV, and that if it did escape from there, we figure out how.
The many many calls like those you highlighted above are asking for a thorough investigation into WIV to answer these questions.
If the virus did originate/ escape from WIV (which is considered to be highly unlikely), then either
A) safety protocols were not followed at a level 4 lab
Or
B) CV19 got past the safety protocols.
Both of those are incredibly scary possibilities that need to be thoroughly assessed.
Reiterating, NONE of those scientists are claiming manufacturing of virus. They all want safety questions answered, and China is not being forthcoming with answers or allowing outsiders in.
China’s lack of compliance with international safety study groups is the real scary thing here.