Can you sue? Of course. Will you win. IMO, you have little chance of winning.

Whether to be worried is not something we have an opinion on. But if you get everything brought up to date, the court may dismiss it.

Can you sue? Yes. Will you win? i think it is doubtful based on what you wrote. If you win, does he have any money to collect? Probably not.

Nothing in your post states grounds for a lawsuit. Just go elsewhere.

They are not responsible for the acts of third parties.

Oh yeah. All sorts of trouble..........................

This is a Q&A forum. You have not asked a question.

This is entirely permissible, and appropriate..........

If you recorded it, you likely broke the law. The only person to address this to is your lawyer.

Nobody has the "right" to "forge" anything. Whether that is what happened here is unknown.