Let's not continue the Diana-Camilla blah blah. Diana's been dead for 12 years now. Let it (and her) rest.
As to the brooch (/brooches?), we have information from the generally reliable RJOTWMB stating there is one, and we have information from The Lady Diana Discussion Board in August this year quoting royal jewels author Leslie Field, who stated there are two. However, the poster who provided the RJ information is regarded highly so maybe Ms Field (if quoted correctly) is mistaken or is referring to another set of brooches.
The other "new" information is that Diana's jewellery was divided three ways after her death. We were aware that the "important" pieces went back to the Crown, ie the Queen, and the remainder or bulk were left to William and Harry. Now it is stated that some jewels (or at least one) were returned to the Prince of Wales. As far as I'm aware, and I could be wrong, this third division hadn't been mentioned anywhere previously.