If I recall correctly, there was a 2 year rule. that if the person had not been audited by the orgs for 2 years then a field auditor could take the person as a pc.I don't think you're ever going to find an org that would give the folders of one of their public to a field auditor. That's the "reverse" way this is supposed to go. Field auditors are supposed to bring public to the org, not the other way around.
The only exception I could think of is if the field auditor is working on a recovery cycle for the org; getting an "ARC Broken" pc recovered. But the idea would be the pc gets recovered to the org. The field auditor isn't supposed to keep him.
And, as others have said, good luck getting the org to give your folders back. I can't see it happening unless you file a lawsuit or something.
Even then: I'm sure the org could give some reason the folders belong to them, not you.