As expected. You have a choice now. Either try an IAS appeal or wait and see if/when they send a Letter of Claim (LoC). They have been warned that if they pass your details to a third party DRA they will be considered in breach of your GDPR which is something you can use later, if necessary.
If they do pass on your details, you can expect some debt collector letters which you can safely ignore. They are powerless to do anything except to try and scare you into paying. Ignore them.
If/when. They do issue a claim, it is to your advantage as a judge in the small claims track of the county court is the ultimate dispute resolution service. Any claim is easily defended.