If you don’t answer their questions, they will calculate what they think you owe, and charge you for that. It will probably be larger than what you would normally owe if you just reported. They can also just audit you and subpoena all your records, and throw you in jail if you don’t comply.
That all assumes I have a job. -- LOL
Ohhh... you're going to throw me in jail and give me three meals a day and a place to sleep that's out of the elements!