System Restore hung, now no mountable boot volume

I was working on a Win 10 X64 Home PC for some friends and thought I'd try a System Restore. It started the restore ok then got to System Restore initializi9ng and hung there for several hours. I finally had to drop power.

When I powered it back up the hard drive is no longer available. I get a unmountable boot device.
DISKPART doesn't see it, Macrium Reflect doesn't see it.

What about EaseUS Partition Recovery? Might that work? Can I run it from Kyhi's WinPE disc?
Any other alternatives to repair the partition table/MBR? TestDisk perhaps? @NavyLCDR?

Coincidentally, the drive may have failed.
Boot into Setup (Bios) is the drive listed there? If not it has failed.
If Diskpart does not see the drive, it most likely has failed.
Download the ISO image for Seatools, burn the image to CD using IMGBurn or to a USB Flash Drive with SeaFlash, all available in my signature. Boot off of the newly created media, run the Short and Long tests on the HDD, if either test fails, the HDD needs to be replaced.

SEatools passed okay.

I'm going to try EaseUS. Any other suggestions welcome.

The reason the disk was not visible to any of the tools was because it was in RAID mode instead of AHCI. Once I put it in AHCI I could access it to run chkdsk (which fixed a few problems) and Macriums's Fix boot problems, but it wouldn't boot. I put it back to RAID then it booted but I was back to the BSOD. BSOD is not creating a dump even though it's setup to for small dumps.

I put it back to AHCI and am doing a Macrium image backup then I will wipe it an do a clean install in AHCI mode of Creator update, apply all updates then restore data.

Edit: All is well now. Install completed and activated, and it's in AHC, not RAID. All data in Windows.old. Will install updates tomorrow, restore data and return the PC to owners.