Yes. The occasion in March 2019 was to mark the 50th anniversary of the investiture of the then Prince Charles as the Prince of Wales. The Queen, Duke of Edinburgh and the Duke and Duchess of Cambridge were to view items on display from the 1969 Invesiture. Everyone else (including the Duke and Duchess of Sussex) were to wait in the main area where a performance of a Welsh Childrens Choir took place and this was followed by a Reception which Welsh charities, organisation and businesses attended.

In this video you can see the whole fiasco unfold. Both the then Prince of Wales and Duke of Cambridge were furious with them. The late Queen totally ignored them. Eventually an equerry 'escorted' them out while the other were looking at the displayed items.