I've just received an email from my friend at the estate agents. He claims to have found an electrician who is willing to issue an EIC for him. It is not the same electrician who did the original installation.
I hope the 'electrician' understands he can't have any limitations at all so had better be confident that every millimetre of the installation is fully compliant.
If it hits the fan later it's his name at stake and his backside in court. Fool.