Once again, you are speculating. "going from a given", you are assuming that they are there, but you don't know. So you are speaking about facts that you cannot prove. This is exactly what you are claiming other are doing. We've yet to find out if they have successfully contained any risk until there is adequate time for person to develop symptoms. The incubation period can be anywhere from 2 to 21 days. We're not there just yet, so don't assume we are in the clear just yet.
I've lost no steam as you have yet to still produce any proof that what you say is factual. You are giving your best guess at what happened. You giving us your opinion on what you expect to be reasonable security measures could sonly provide a false sense of security that could have potentially not been there. You claim to desire fact but provide none of your own.
The only thing I'm fishing for here is for you to admit you know nothing more than anyone else. You are simply providing your opinion of what you think happened and presenting it as factual information. Just admit that you are arguing for the sake of arguing.