Wow. That’s a real shocker of a case.
I suspect one of many that probably are not reported on.
In my own case, a very simple one compared to this one, and mortgage free, with no loans to anyone, buying with cash only, I got a letter out of the blue from a debt company quoting to work for O2.
Long story short, it apparently related to a phone account closed 2 1/2 years previously, with O2 making a payment to the wrong account, keeping mine open when they should have closed it.
My point is, the debt collection company were particularly aggressive over a small amount of money, (£200 or £300), letters, phone calls, even a phone call to my daughters phone (a number that can only have been supplied by O2 based on an address search of their system).
I asked them to list the debt and the dates involved, oh no they said, its up to me to prove I don’t owe the money!
I tracked it all down by looking at previous bank statements and discussing directly with O2…..eventually. (What a pile of>>>> their ‘customer service’ is).
No apology from either party mind.