Yeah I got the same response originally (nothing been logged previously, supposedly). One of the reasons why I questioned them in the first place was because I saw others having the same issue, 1 in particular where he called out Audi on Twitter and Audi UK customer services responded to him publicly (I also commented on that thread). I get a sense that there is poor communication internally within Audi, both dealership and Audi UK. I actually spoke to Audi UK again yesterday for an update on the issue and they said a manager would get back to me.
Like Gareth says, it's up to the individual whether to pursue or not. Even though I don't own the car anymore, I'm still happy to chase them, I will let you know if I have any breakthrough with the issue.
Alex