It seems like this is getting a heck of a lot more complicated than it has to be.
1. Mount the Windows 10 ISO file. Mine is called Win10_1607_English_x64.iso because I downloaded it directly from Microsoft. When mounted it will open in it's own drive letter (virtual DVD). Mine opened in H: drive.
2. Look in the new drive letter, mine is H: drive, Sources folder. See if there is an install.wim or install.esd file. It needs to be install.wim. If it ain't install.wim then just download the official ISO file from Microsoft:
Windows 10 ISO
3. Once you have the ISO file mounted, and once you have an install.wim file in the Sources folder of that mounted ISO file, then right click on the start icon, select Command Prompt (Admin), and run the following command:
Dism /Online /Cleanup-Image /RestoreHealth /Source:H:\Sources /LimitAccess
The drive in red is the drive letter that resulted from mounting the ISO file.
That's all there is to it:
In the time it took me to compose this post, it was done on my computer.
C:\WINDOWS\system32>Dism /Online /Cleanup-Image /RestoreHealth /Source:H:\Sources /LimitAccess
Deployment Image Servicing and Management tool
Image Version: 10.0.14393.0
[==========================100.0%==========================] The restore operation completed successfully.
The operation completed successfully.