I know the How Many Left site has its limitations but it does provide a clue about overall quantities - at least we know roughly how many we are looking for.
Also aware that we don't get VINs in UK ads - but I didn't realise you do in the US - I just thought dealers were much more obliging about such info. than in the UK.
Unless they're specialists, some UK dealers are not really interested - to them, any XF is such a minority interest car that they just want to flog it and forget it. Many know next to nothing about it, no wonder they don't sell quickly - it's not just the price...
The UK market has traditionally been so European and Far East dominated, it's perhaps not surprising (especially in the performance sector) that the XF struggled for mass-market recognition here - except to the enlightened, of course!