Thanks Beth for providing these images and the compilations.

QEII's has a distinctive bend on the right prong and Queen Camilla's has a gold root ball. So these two are definitely unique.

The more I look at them, the more I think that the brooch used by Diana and Catherine are the same.

They seem to have all the same shapes and "twists" to the prongs.

All just speculation - but they look the same to me.