Inaccessible boot device Winclone 9, Big Sur

Hello, I currently attempted to clone windows 10 boot camp partition to an external ssd (Samsung X5 Thunderbolt 3). I am using your most current Ver. I used “add Boot Camp drivers” to no avail.
same error Inaccessible_boot_device when launching Windows.
I even went as far as to find a working copy of windows 10 on a different ext ssd (non thunderbolt 3) that operates on this iMac made an image of the drive using win clone then restored to thunderbolt ssd. still Inaccessible_boot_device.
tried booting in safe mode, with and without command prompt, still the same error
any thoughts to get this working?

My device.
iMac 3.8 5k 8-core intel core i7
macOS Big Sur Ver 11.5.2

It sounds like the mac firmware doesn’t support windows booting from that interface or drive.