No offence of shoplifting was committed, but the offence of fraud by false representation was (as it doesn’t have to succeed : the attempt that exposes another to risk of loss suffices for the offence to be made out).
However, I agree with Will, it is unlikely this will be pursued (If it was a one off!), as action would have been taken at the time.
If it were part of a continued course of attempts, then they might be bothered to go back to check CCTV / card receipts, but unlikely for a one-off.
Don't cause yourself stress unduly by trying to go into too much detail with this. Just identify your key defence points and list them, with maybe a brief explanation for each one. You have at least four compelling arguments that I can think of off the top of my head. Make lack of authority the last one, as it's the "if you don't accept any of the aforementioned points, this one is the killer" argument.
P.S. regards to this... "Thanks lookinforinfo, I will print it out and try and show to Judge" - don't attempt to show anything to the judge or Claimant's rep that isn't included in yours or their WS. You'll get your knuckles rapped and it may not do you any favours in the eyes of the judge. Just keep it simple and stick to presenting your arguments concisely, supported by the content (or lack of) within either WS.
Don't touch them owe me £500 since January 2019 make excuse after excuse. Seem they always have software problems sending money out. Keep saying they will call back or email nothing been chasing it now for 6 mths the phone staff always have the same banter we will chase it up and get back to you then nothing!