Hey Beckett,
I too bought an official retail version of Windows 10 for my nMP. It should still work. Again, I know it's a pain, but it might be worth trying over again - i.e., either using Guru3D to remove all the drivers, or making a whole new Windows 10 Partition.
Without CCC I doubt you have CrossfireX working. I know CrossfireX didn't work on my computer until I got CCC installed, restarted the computer, had Windows do a minor AMD update, and then restarted again. I then had to enable Crossfire in CCC.
I Tryed the Guru3D uninstaller option an redo the whole process again. But That didnt change anything.I am still stuck with this AMD update error.
Actually it was so tricky having windows 10 installed on thunderbolt drive that I prefer waiting.