You are only liable as the Keeper if the PCNs issued were compliant with all the requirements of PoFA.
You say you know that your daughter has "accrued a fair number of tickets". How were you aware of this? Those "tickets", depending on whether they were windscreen Notices to Driver (NtD) or postal Notice to Keeper (NtK) are crucial to determining whether the PCN is fully compliant in order to be able to hold you, the Keeper, liable for those charges.
You need to dig them out or at leat find one or two if they are all for the same location. There would also have been reminders and debt collector letters, but these are not required. It is sight of the initial NtD or NtK that is important.
Please show us the N1SDT claim form. Only redact your personal information, the claim number, MCOL password and the vehicle VRM. Leave everything else, especially all dates and times visible.
What is the issue date of the claim? Don't do anything else right now if it has been issued within the last days. You only need to submit the Acknowledgement of Service (AoS) by following the instructions in this document:
https://www.dropbox.com/s/xvqu3bask5m0zir/money-claim-online-How-to-Acknowledge.pdf?dl=0As the claim has now been issued, you should send an SAR to the DPO of Park Watch.