If you believe McDonalds in this analogy should be investigating the origins of Chipotle's problems as opposed to resolving their ongoing issue then we'll just have to agree to disagree.
Are you serious?
Ok but they can do both, right? I mean, I can improve my performance by looking at my own performance, but also watching others.
Moreover, the US can exert a lot of pressure on other countries to meet certain standards and reduce risk. Knowing what went wrong will help determine standards.
It's not like lab-leak-causes-disease only happens once. This happens all the time, just like aircraft incidents. If incidents weren't investigated and tracked, planes would be riskier than they are.