How do I set a custom default accent color during deployment of Windows 10?

When deploying Windows 10, I am able to set a partial custom theme using the settings in unattend.xml as follows:

 <settings pass="oobeSystem">
  <component name="Microsoft-Windows-Shell-Setup"
             processorArchitecture="amd64"
             publicKeyToken="31bf3856ad364e35"
             language="neutral"
             versionScope="nonSxS"
             xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State">
   <Themes>
    <BrandIcon>%SystemRoot%\Brand\CustomThemeIcon.png</BrandIcon>
    <DesktopBackground>%SystemRoot%\Brand\CustomDesktopBackground.jpg</DesktopBackground>
    <ThemeName>Custom Corporate Theme</ThemeName>
   </Themes>
  </component>
 </settings>

I'm looking for a way to set default accent color to something that complements my custom desktop wallpaper instead of the default periwinkle blue color. The user interface for this setting in a running installation is Settings app > Personalization > Colors > Choose your accent color. I am perfectly happy to choose from the provided color palette, but I don't know how to specify it during deployment so that it becomes the default for all new user accounts along with the custom theme.

I thought the WindowColor element might do it, but I haven't been able to find documentation for it in Windows 10. There is documentation for it in Windows 7 and 8 on TechNet and MSDN, but there were differences between those versions and no indication about what values to use in Windows 10 or if any values will even work. I tried <WindowColor>Color 1</WindowColor> just to see what would happen, but I did not get the desired result.

I tried configuring the color I wanted in a running version of Windows, extracting all the relevant values from the registry, and applying them in Windows PE to the appropriate places in HKLM and HKCU of the default user profile in the target OS in Windows PE prior to the first boot after install.wim was applied to the disk, but this did not work. As part of the first boot and first logon processes, my values were overwritten.

I also tried creating a custom theme and setting it as the default theme by changing registry references to aero.theme to my custom theme, but this still did not accomplish my goal.

I'm stumped. The default accent color looks terrible with my desired custom desktop wallpaper. How do I set a custom default accent color during deployment of Windows 10?