App Bundle targets unrecognized languages: cb Error

Question

I am trying to build a Xamarin project using a package from Facebook and attempting to upload it to the Google Play Store. I think that the Facebook SDK is generating the cb language files and causing the upload to fail. The suggestion that I've gotten from the Google Play Console is to exclude invalid languages by third-party libraries using resConfigs. But because this is a Xamarin project, I don't have any gradle files.

I have tried creating a .resfilters file and using <AndroidResgenFileLists> to add it to the Android.csproj file but it doesn't seem to work.

These are the 2 variations of the .resfilters file I've tried.

<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <ItemGroup>
    <Filter Remove="values-*" />
    <Filter Include="values-en-rUS" />
  </ItemGroup>
</Project>

<?xml version="1.0" encoding="utf-8"?>
<root>
    <exclude name="values-*" />
    <include name="values-en-rUS" />
</root>

Any help would be much appreciated!