as a few have said, if you had co opperated and answered all the questions, you would have drove off with out an issue.

they asked you a few questions and you didn't/couldn't answer them with the details, they may have assumed you had no insurance, and your lack of information would have just confirmed what they thought.

regardless of whats wrong with your car/ documents, if you pass the attitude test you have a good chance of getting away with the odd thing.