What you describe is a medical malpractice case. There might be other causes of action if there are facts warranting a legitimate cause of...

Unless they caused damage due to their breach of the standard of care, you would have no valid claim.

The attorney’s information should be in the documents (or online). Make sure any agreement made is in writing.

Yes they can. The loan becomes completely due on death. You will need to get a new loan.

No it is not permissible unless specifically allowed by the fee contract.

Look into State Bar Fee arbitration https://www.floridabar.org/public/consumer/pamphlet009/

Writing of a debt, or a determination by the credit card company does not extinguish the debt. You can still be sued.

It may be a scam. Whenever one is unsure, give no information, demand proof in writing (do not give your address or other information),...

A civil litigation or debt defense lawyer, or yourself, can do a motion to set aside.

If you file against them they may be willing to settle for a dismissal with prejudice.