The conditions of parking were that the driver should input their car reg at the hotel reception. The driver didn't, for whatever reason. The car was in the car park 22 minutes. The driver that. enters the private land is always liable. CE didn't know the identity of the driver so they used "reasonable cause" under the KADOE rules to request the keeper details from the DVLA and then sent the NtK to the keeper.
So, where are we now? The keeper has made the error of admitting that they were also the driver. Unless the NtK was fully compliant with the strict requirements of PoFA (often not), had the keeper not identified the driver, CE would have had little to go on.
The only things you can appeal on at POPLA are the signage and maybe contractual right for CE to issue PCNs. The signage is sometimes a winner at POPLA, especially if you can show that any signs are not prominent or obvious or are obscured. Also, any signs must adequately bring to the attention of the driver the charge for breaching any conditions.
The contract with the landowner may be of value. It is interesting that the sign shown is in the name of the hotel. It would need to be clearly established that CE has the right to sue in their own name. They may lack the right to sue in their own name. You would not know though unless you get to see the contract.
The sign is the contract between the driver and the landowner. The Contract (Rights of Third Parties) Act 1999 in the UK allows a third party to enforce contractual terms if the contract expressly provides for this or if the terms purport to confer a benefit on the third party. The sign shown doesn't include any clause that allows a third party, Civil Enfocement in this case, to enforce the terms.
If the third party, CE, is acting as an agent for the landowner, they might be able to enforce the contract on behalf of the landowner. The relationship between the landowner and the third party would need to be clearly established. This is what you are relying on at POPLA. They must provide evidence that they have the right to enforce the contract between you and the landowner. This will be in their own contract with the hotel. You would have to insist that they provide a copy of the contract between CE and the hotel, not just a statement say that they do.
The hotel may assign their rights under the contract to CE. This assignment needs to be clear and appropriately documented.
For CE to successfully sue for a breach of the parking contract, the terms and conditions on the sign should clearly state that they are authorised to enforce the contract. It doesn't.
CE must demonstrate that they have the legal right to enforce the contract, either through privity, third-party rights, agency, or assignment. They will have to evidence this at POPLA.
So, whilst you have thrown away a few additional arguments you could have used at POPLA by revealing the drivers identity, you should still appeal to them. If you are unsuccessful has no bearing on how you proceed after that.