Not familiar with the details of this case but I should just point out that this 'You've got something on me? I'll get something on YOU' is part of the wharp and weft of British life, I think it's based on the way American lawyers - and now probably all lawyers - work.
South Yorkshire police did it with the Hillsborough victims of course back in 1989, and persisted with it. In fact, the sure fire way of getting the State to harass you is to be wronged by them, be it the police or your local Council, because they'll follow it up by getting a file out on you, subjecting you to surveillance and gathering dirt.
Surrey County Council did it to me after I whistleblew one of their care homes which nearly killed my mother back in 2014, they literally spent years devoting their time to getting dirt on me; as far as they're concerned that's what they're paid for, and not Safeguarding their dodgy care homes - but as I say all this is based in that legal way of doing things. Simply accuse the other person of something, often the very thing they're accusing you of!
Some people reading about this latest legal move will be thinking, well, it's six of one and half a dozen of another, and a doubt is as good as a win, the thinking goes.