My father got an award from the Governor General at Rideau Hall and a lot of what you are talking about is as much about organisation and control over guest lists than anything else. Only my mother could attend, for instance, so her name and invite was for her only and not allowed to be transferred.
Hell when my husband had his citizenship ceremony in Ottawa they are very very specific about number of guests, time to arrive, where to enter, etc...
That's just typical anal Canadian government oversharing and over planning and making everything seem so f**cking formal and scary that you think if you fail to follow instructions and sign your name in the wrong place (or show up at the wrong door) you are committing a federal crime. I mean just filling out your taxes or applying for a passport can put the fear of God in you with threats that if you mess up you go to the back of the line and have to start all over
But since this is all about Camilla attending the same event as Jeremy Clarkson that event took place BEFORE Clarkson wrote that vile piece. So at that stage would he have been on anyone's radar? As for Piers Morgan he is press and a cockroach sycophant so he will be everywhere. There were A LOT of British stars at that luncheon so I don't know that Piers sitting at a table somewhere amongst a crowd would stop me from attending a luncheon where Judi Dench, Maggie Smith and a slew of others were going to be. I don't have to talk to him... And it's important to keep in mind that despite what clickbait tabloid misleading headlines suggest it wasn't her luncheon, she didn't make the guest list AND those were two men (or ONE man considering the timeline) out of a lot of really interesting British celebrities who were present.