Send three and fourpence, we're going to a dance!
If the driver has been identified, then the paperwork - whether the original NtK or the NtD we have been shown is irrelevant - such notices are only relevant to keeper liability when the identity of the driver is unknown.
The most relevant thing in the paperwork linked is that it has told us a key part of the story that you neglected to. If you can't or won't tell us what happened, you are simply wasting our time and your own. I am less concerned about the latter.
The obvious question mark, regarding the case, as opposed to the OP) is the signage - what it says and whether it was "there to be seen".
