Ah! Our earlier discussion which I had forgotten. Yesterday when I looked at The Crown Jewels 1998 I noted it mentioned the recutting for the QEQM crown. I do treat that source as a rather reliable one. Must dash out now but I will reread it all later (about the K) and report back here.
However, it is sad to think that the K would not now fit into its two settings (that I think of), being the surround of rose cut diamonds, and the honeysuckle brooch setting.