My vouchers were IC Rewards "F&B vouchers" as I'm not in the Ambassador scheme. I no longer have the letter I received as a Diamond on the bog-standard IHG Rewards Club scheme, but don't recall seeing mention of Kinaara being excluded.

Anyway life is too short. As suggested above I think the points compensation, while leaving me out of pocket, does appear to be as good as it is going to get so I consider it a win.

Thanks everybody for your thoughts on the issue though - all very much appreciated!!