You haven't receive a Notice to Keeper (NtK). What you have shown us is a Notice to Driver (NtD).
If CPP want to hold the Keeper liable because they have no idea who the driver is, they must fully comply with all the requirements of PoFA. One of those requirements is that they must not request the Keepers details from the DVLA and send an NtK before 28 days have passed since the alleged contravention. Also, the NtK must not arrive any later than 56 days after the contravention.
It is possible that CPP may not want to rely on PoFA at all in which case, it's a guaranteed win for the Keeper as long as the drivers identity is nt revealed inadvertently or otherwise.
For now, you are getting on with Plan A which is trying to get PALS to cancel the PCN. If/when the NtK arrives, we will look at it and decide whether PoFA has been fully complied with.