UPDATE
Unfortunately the TEC appeal was rejected and we received a rejection letter two weeks ago. The grounds were that failing to update the log book is not a valid reason. Very frustrating.
The worst part it, my partner tried contacting Islington council for any follow up action with no avail but didn't tell me that was the case.
And today we woke up with a bailiff from the CDER group knocking on our door.
It was quite embarrassing of course and we decided to pay £575 (originally the claim was £325) to get them out of our doorstep.
I have no idea if there's any follow on action that we can take apart from the hard lesson learned.
Thank you for all your help as usual.