Yes you can but there may be reasons not to. Consult with experienced criminal defense attorneys. Use the Avvo search tool to find an attorney....

It sounds like you need to consult with other attorneys to take over your case. Use the Avvo search tool to find an attorney....

You may have a valid basis to dispute these attorney fees.

Research attorneys in the area and then contact the attorneys. Use the Avvo search tool to find an attorney. https://www.avvo.com/find-a-lawyer

The insurance company has an argument that there is an accord and satisfaction (depending on prior communications) making you unable to get more...

If the case was settled, the documents you signed would have released everyone.

No, there is no requirement and it does not relieve you of the debt.

Insurance lawyer. Get the gap insurance policy and ask an insurance lawyer to review.

Find the court where it was filed. Review the case file. File a motion for an Order to release the funds.

Definitely. She wants the car back and did not tell you about the lien. You should immediately get all your money returned.