personal jurisdiction

If your credit company made an investigation and already decided to give you a refund, they should have some record.
Your case raised a very interesting legal issue: personal jurisdiction. The company as the plaintiff may have a hard time to prove that a local court in its state has a jurisdiction on you. They may sue you in a court where you reside. However, I really doubt they would take that trouble to sue for a few hundreds dollars.
This type of disputes usually end up a record on your credit report which may have some adverse effect on your personal credit history. You may resolve it by presenting evidence to the credit buearau.