Not finding deleted images on memory card

[Marriner]

I deleted about 1500 images from my Sandisk 32GB CompactFlash card (Extreme, UDMA 7, from a Canon 5DIII camera) using a Sandisk USB3 card reader on Windows 10 Pro. About 500 of these images should not have been deleted. I immediately realised my mistake and the card has NOT been written to since. I have run Recuva using every conceivable option and the 500 photos are not found at all. The first 1000 or so I deleted date from a couple of months ago and they are all found. The last 500 (the ones I need) are from yesterday and simply do not show up at all. I have also tried other programs (Pandora, Unerase, NTUndelete etc) and none of them find these files either. Has Windows done something to the FAT table to stop these files being found? Why doesn't a deep scan find them when the card hasn't been touched since? Many thanks for any assistance.