Hello,
I've replaced the old RAID card with one that is compatible with Windows 10, installed the new drivers, moved the mirrored RAID1 drives to the new card, and removed the old card.
Attempted to upgrade Windows, it fails on first reboot, then reverts back to Windows 7. Exact error as before and seemingly the same problem. I tried using a program called Ghostbuster to remove the old rr172.sys driver that was causing the problem before but it renders the computer unbootable when removed. Manually copied it back to C:\Windows\System32\DRIVERS\ from the backup.
Any advice? I re-ran the FRST program and attached new versions of these files.