Can't Package Plugin that Uses PlatformFileManager

When trying to package a plugin that has C++ code using the class FPlatformFileManager, the UnrealBuildTool gives me:

error C2653: ‘FPlatformFileManager’: is not a class or namespace name

I can build the project, including the plugin, using Visual Studio 2019. I can also drop the plugin folder into other projects and use the plugin. I just can’t package it.

I’ve tried whitelisting only Win64 in the .uplugin file, but still get the error.