> That version of the virus can't be massively different from Cov-19.
Yes it can. Labs specifically study, and propagate, mutations. A lab can do in years what might take nature decades. If it did originate from a lab, we very likely would never find a close enough progenitor in nature to know where things started (what strain the lab started with).
We can trace mutation histories of viruses very extensively, the tools and techniques for this are now pretty sophisticated, so that's not necessarily an insurmountable obstacle.
There is a probabilistic aspect to this though. If we happen to find the exact wild virus population Cov-19 originated from (whether it then mutated naturally or in a lab) then I think we'll nail it. On the other hand if we just find an adjacent population that diverged from the actual Cov-19 source some time ago it could be harder to pin down the route.
They probably meant RNA code of the virus. Since if you know it you can produce it in a lab and introduce it into cells and they will manufacture functional copies of the virus.
It's not a recipe to create virus in a lab. It's a recipe to manufacture copies of the virus in a lab.
