Although the heat shield does not affect the running of the vehicle, it is not wise to run without it. The teamoerature can exceed 500 degrees and be a fire hazard. Temperatures of that range have been known to cause fires, by vehicles driving in dead or dry grass.
Catalytic converters do not rattle. If it does it will need to be replaced as it may block the exhaust. Loose heat shield?
No, that will not work. A restricted catalytic converter will need replaced.
There's no possible way to pass inspection with a bad catalytic converter, if if you find out you have a bad catalytic converter during your inspection you have a chance after you after you have replaced the catalytic converter and the inspection no no charge/free!!
If it came from the factory with a catalytic converter then it must have one
they are usually bolted on in the front of the converter.
Catback is shortened slang for "everything back from the catalytic converter". It is a bolt on exhaust which connects to the rear of the pipe holding the catalytic converter, and ends with the muffler and exhaust tip. In short, you need a cat to have a catback.
To pass emissions you do.
If it came from the factory with a converter then it needs a converter.
Yes, legally and for the computer to function correctly you will need a catalytic converter.
Yes, it is illegal to operate any vehicle that came equipped with a catalytic converter from the factory with it removed.
Legally, yes
No. you'll need to get a replacement.