Did you try ahci? Unless raid is actually needed I never use that. There should be no secrets as I've never had an issue with any Dell system old or new optiplex or precision installing a uefi / ahci ssd with win 10.
Make sure bios is set to secure boot off, legacy option roms disabled, bios set to uefi and sata operation set to ahci. Make sure your install media is set for uefi as well. I always use rufus to make my iso bootable. If this works and hopefully you haven't already tried everything I just mentioned make sure to delete any and all partitions off the drive and let windows do its own thing on a totally blank drive. Worst case is something is wrong with the drive. There have been cases that I had to use gparted to access and clean a drive. Not sure why but windows disk management won't always detect a drive when there is a problem.