Your points are well-taken, but here's the thing - none of us here are epidemiologists (actually, I take that back - I think there is at least one active member who actually is an epidemiologist). None of us are locked in on this anywhere near the level that the CDC is.
All of those things you listed above - as I said earlier, you can clutch your pearls about all of the "what if"'s until the cows come home, but the fact of the matter is that the people at the CDC are not naive fools; they know about the Chinese government's control of information. I guarantee you that they are not taking any information released by Beijing as a given. All of the stuff you listed above is already "baked into" the CDC's most recent guidelines.
And as of today, they are not calling for any drastic changes for the public as a whole. They describe the immediate overall health risk to the U.S. as low. The guidance they are giving - other than not going to mainland China - is pretty standard stuff: wash your hands; cover your mouth and nose with your sleeve when you sneeze; avoid sick people who were recently in China, especially if you're very young, very old or already have compromised health. The public is not being told to don face masks or stay indoors. The public is not being told to avoid large crowds, air travel or cruise ships.
Yes, the situation is fluid and it could change, but honestly, if the CDC thought there was something major that China was withholding - something that could drastically impact the nation's health for the worse - we'd be getting a lot more stringent guidelines than we've gotten so far.
I think I've made my point by now. Some people may disagree with me, and that's OK. I don't need to keep going back and forth to prove anyone "wrong" just to make me feel "right". It's merely my opinion.
Signing off.