To be honest, in this particular case, I would ditch the defence you have set out.
Is this instance the Claim Form states that they are pursuing you as driver.
The is no stated alternative pursuit as vehicle keeper under PoFA 2012.
This means that their claim can never succeed assuming what you say is true.
So you could simply set out a very simple defence which states;
I deny the claim in its entirety and no debt is owed.
That the information set out in the PoC on the Claim Form are imprecise but I will do my best to engage.
It is accepted that I was the Registered Keeper of the vehicle, stated on the claim form, on the date in question.
That this is a contract dispute and, as such, there is no legal requirement for a Registered Keeper to reveal any driver details to an unregulated private parking contractor.
That I will not, under any circumstance, be revealing the drivers identity and, as such, no assumption can be drawn by me exercising my legal right to remain silent in that respect.
I may rely on the persuasive Appeal Court case of VCS Ltd v Edward [H0KF6C9C] if required.
That the Claimant appears to have no evidence which proves who the driver was.
That the Claimant is therefore unable to demonstrate that I am liable for any charge or debt.
The claim is therefore denied.