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You would effectively dispute the debt as not being legit, using whatever case law that supports your assertion, and if it is verified upon dispute, you then acquire the right under FCRA 623(c) to file a civil action contesting the reasonableness of the investigation by the furnisher, and get the matter before a court for an order of deletion.
I doubt that a CRA is going to unilaterally make a ruling that the debt is not legit.
You can make the attempt, but if the furnisher verifies the legitimacy, it may require court intervention.
File a complaint with the CFPB against both the CRA and Cashcall.
https://www.consumerfinance.gov/complaint/getting-started/
Do be prepared for a lifetime of harassing phone calls from zombie debt collectors calling you, your family, even my brothers ex-wife looking for me threatening I was being served with papers at my home or office. It bounces from zombie debt collector to zombie debt collector and I still get calls one last week. Countless others blocked by my various robokillers and block lists. My debt like yours illegal in my state, past SOL and IIB so they can GF#.