As long as it has not been paid and they have the title, it can still be repossessed. If you have the title, then it is safe. If you do not have the title, then it will be difficult for you to ever get rid of it.
The lien on the vehicle was not affected by your discharge. You don't get to keep a car for free just because you file a bankruptcy case. They ate entitled to repossess.
If you are correct that a lender cannot repo a car after a charge off because of the tax code in your state, then you should send a letter to the creditor demanding that they release their lien and send you the title. Filing a bankruptcy that got dismissed does not affect the rights or obligations of anyone. Otherwise, you should try to find a lawyer to help you or surrender the car.
This response is intended to give a general overview of the law and should not be treated as legal advice. There are too many factual issues and exceptions in the law to provide definitive conclusions about your circumstances.
As a rule of thumb, legal advice from the DMV is generally not very solid. Charge-offs don't change this secured creditor's remedies or rights. You have their collateral and they have the right to get it back. Best advice: arrange for a convenient pickup of the vehicle, and whatever you do, do not hide it or otherwise try to thwart, impair or otherwise hinder the rights of the creditor.