What is the relevant clause in your hire agreement about paying PCNs, etc.?
I don't think the OP has answered this question?
There was an argument on this website that if hire companies have a term in the hire contract allowing them to pay PCNs without referral to the hirer, then such a term would be an unfair term under s63 of the
An Act to amend the law relating to the rights of consumers and protection of their interests; to make provision about investigatory powers for enforcing the regulation of traders; to make provisio...
insofar as such a term prevents the hirer from exercising their legal right to challenge the PCN, and therefore the term is legally unenforceable by the hire company against the hirer.
So in theory the hirer would be able to recover any recharge from the hire company.
Whether this argument has been properly tested, I don't know...