Packaging Fails When Media Player->Open Source is Used in C++

When attempting to use a media player asset in code, packaging will fail with the error message shown below.

This occurs even if the Desired Player Name is set, and after ensuring the plugins are included.

1. Open the editor
2. Import a video
3. Create a new media player and media texture
4. Create a new Actor in C++
5. Copy the following code into the .h

   
   class UMediaPlayer* TestMP;
   
   class UMediaTexture* TestMT;
   
   class UFileMediaSource* SourceFile;

6. Copy the following code into the .cpp

   #include "MyProject2.h"
   #include "Runtime/MediaAssets/Public/MediaPlayer.h"
   #include "Runtime/MediaAssets/Public/MediaTexture.h"
   #include "Runtime/MediaAssets/Public/FileMediaSource.h"
   #include "MyActor.h"
   
   
   // Sets default values
   AMyActor::AMyActor()
   {
    	// Set this actor to call Tick() every frame.  You can turn this off to improve performance if you don't need it.
   	PrimaryActorTick.bCanEverTick = true;
   
   	static ConstructorHelpers::FObjectFinder<UMediaPlayer> MPAsset(TEXT("MediaPlayer'/Game/FirstPersonBP/TestMP.TestMP'"));
   	if (MPAsset.Succeeded())
   	{
   		TestMP = MPAsset.Object;
   	}
   
   	static ConstructorHelpers::FObjectFinder<UMediaTexture> MTAsset(TEXT("MediaTexture'/Game/FirstPersonBP/TestMP_Video.TestMP_Video'"));
   	if (MTAsset.Succeeded())
   	{
   		TestMT = MTAsset.Object;
   	}
   
   	static ConstructorHelpers::FObjectFinder<UFileMediaSource> MSAsset(TEXT("FileMediaSource'/Game/FirstPersonBP/Unreal_MP4_TestVideo.Unreal_MP4_TestVideo'"));
   	if (MSAsset.Succeeded())
   	{
   		SourceFile = MSAsset.Object;
   	}
   
   	TestMP->OpenSource(SourceFile);
   
   	TestMP->DesiredPlayerName = FName("WMFMedia");
   
   
   }

7. Compile
8. Drag the media texture onto an asset in the level
9. Drag your actor into the level
10. Attempt to package the project for Win64

Result: Notice that you'll get an error message along these lines:

Expected: Packaging would complete.