Sadly all of those are out...
The Ogilvy Tiara is property of Princess Alexandra...her one and only tiara, poor gal.
The Cambridge Sapphire was property of the Duke/Duchess of Kent but was sold sometime after Princess Marina's death. A new tiara was made with the suite's necklace...but sadly that one is butt ugly and still property of the Duke/Duchess of Kent.
The Gloucester Honeysuckle is property of the Duke/Duchess of Gloucester.
The Teck Crescent is reported to be in the set loaned to the Duchess of Cornwall.
The poll has the most likely choices (except for Queen Victoria's Sapphire Circlet) though they may still surprise us with a unknown from the vault. A new to the BRF tiara is highly unlikely considering Bea's position and that all the other granddaughters(-in-law) got loans from either The Queen or their mother(-in-law). New commissions aren't announced they just appear but with the size of the vault are very rare in the BRF...reworking an old piece is more common but still rare and never announced.
I find it strange that Fergie had a new buy..... maybe the era, and the fact she didn’t have a family one like Diana? Or perhaps the Queen saw the writing on the wall way back then? TBH, Fergie was probably the first married-in that didn’t come from foreign royalty, or from the type of family that had a tiara or two in the vaults.
I have a feeling Fergie’s tiara is no longer around, unless it does turn up on Bea.