Were you a patron of the hotel? If so, have you tried asking them if they can get the PCN cancelled? It is likely that the hotel contracted PE to operate the car park.
AS above, you need to be very careful when you talk about this, especially in any communications with the respective parties. There is no such thing as the vehicle "owner" when dealing with contractual issues. How do you prove who the vehicle "owner" is?
All you need to understand is whether you, the Keeper who has received the Notice to Keeper (NtK) have identified the driver, who is unknown to PE unless you, the Keeper, identifies that person, irrespective of whether it is the Keeper or not. There is no legal obligation on the Keeper to identify the driver to an unregulated private parking company and no inference or assumptions can be drawn or made by PE that the Keeper must also be the driver. "Owner" does not come into it.
The driver is liable for any alleged breach of contract with PE. If the driver remains unknown to PE, they can only transfer liability from the drover to you, the Keeper, if they fully comply with all the requirements of PoFA. They haven't, but will never admit it.
Any appeal is likely to be rejected by PE but you may have a chance with POPLA. You can only appeal to POPLA if the initial appeal is rejected and they provide you with the necessary POPLA code.
Aside from the contractual issue of the fact that parking was paid for in good faith through 'YourParkingSpace', and other contractual issues that will be evident when you tell us whether the signs at the location mentioned any requirement to input the VRM into a terminal, this is likely going to go all the way to a small claims track hearing in the county court if PE do not eventually discontinue.
For now, please try and get some photos or confirm what the signage says or does not say on site about requiring to use the terminal in the hotel. Also, please expand on exactly what YourParkingSpace wrote when they said "here is your £8 fee refunded to help towards the cost of the PCN"? Anything you did over the phone is worth about as much as the paper it is not written on.