Thank you all for your comments. I very much appreciate your input. It's these 'gaps' that I want to ensure I cover when I do get the opportunity to respond to SWT. However, that said, the whole incident (even the whole day) seems a blur, hence why I did something so stupid.
1) Were you questioned by the Revenue Inspector under caution? I definitely wasn't cautioned. I wouldn't even say I was particularly questioned. There were words exchanged between the guard and the inspector that I couldn't hear. The Revenue Inspector asked if my husband knew I had his card, to which I said "Yes"