Fatal Error Obj in another map

I have a very strange fatal error, and that doesn’t always happen.

When we package the project (Development / Shippgin FullRebuild + Distribution).

Some of the Blueprints that contains a movie player, the packaging fails.

The error says that a Blueprint is on another map. However that is a lie. It is only on a map. The only thing that can be on other maps is the movieplayer to open a MediaSource. But even creating a unique movieplayer asset for this Blueprint, the packaging fails.

I tried to delete the intermediate and saved folders, but keeps crashing.

UATHelper: Packaging ():   LogCook: Display: Cooking /Game/Test/Movies/MediaPlayer1 -> E:/UE4_WS/Test/Saved/Cooked/Win64/Test/Content/Test/Movies/MediaPlayer1.uasset
UATHelper: Packaging ():   LogSavePackage: Warning: Obj in another map: BP_Sequence_C /Game/Test/Maps/M_Test.M_Test:PersistentLevel.BP_Sequence_2
PackagingResults: Warning: Obj in another map: BP_Sequence_C /Game/Test/Maps/M_Test.M_Test:PersistentLevel.BP_Sequence_2
UATHelper: Packaging ():   LogWindows: Error: begin: stack for UAT
UATHelper: Packaging ():   LogWindows: Error: === Critical error: ===
UATHelper: Packaging ():   LogWindows: Error:
UATHelper: Packaging ():   LogWindows: Error: Fatal error!
UATHelper: Packaging ():   LogWindows: Error:
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ffadd1f9129 KERNELBASE.dll!UnknownFunction []
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ffa8c86881a UE4Editor-Core.dll!FWindowsErrorOutputDevice::Serialize() [e:\UE4_WS\engine\source\runtime\core\private\windows\windowserroroutputdevice.cpp:63]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ffa8c64bc7f UE4Editor-Core.dll!FOutputDevice::LogfImpl() [e:\UE4_WS\engine\source\runtime\core\private\misc\outputdevice.cpp:66]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ffa8ebaf62a UE4Editor-CoreUObject.dll!UPackage::Save() [e:\UE4_WS\engine\source\runtime\coreuobject\private\uobject\savepackage.cpp:4294]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ffa75451c77 UE4Editor-UnrealEd.dll!UEditorEngine::Save() [e:\UE4_WS\engine\source\editor\unrealed\private\editorengine.cpp:4442]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ffa752f412b UE4Editor-UnrealEd.dll!UCookOnTheFlyServer::SaveCookedPackage() [e:\UE4_WS\engine\source\editor\unrealed\private\cookontheflyserver.cpp:3988]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ffa752f6951 UE4Editor-UnrealEd.dll!UCookOnTheFlyServer::SaveCookedPackages() [e:\UE4_WS\engine\source\editor\unrealed\private\cookontheflyserver.cpp:2896]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ffa75301c02 UE4Editor-UnrealEd.dll!UCookOnTheFlyServer::TickCookOnTheSide() [e:\UE4_WS\engine\source\editor\unrealed\private\cookontheflyserver.cpp:2372]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ffa7516493b UE4Editor-UnrealEd.dll!UCookCommandlet::CookByTheBook() [e:\UE4_WS\engine\source\editor\unrealed\private\commandlets\cookcommandlet.cpp:882]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ffa751969ff UE4Editor-UnrealEd.dll!UCookCommandlet::Main() [e:\UE4_WS\engine\source\editor\unrealed\private\commandlets\cookcommandlet.cpp:586]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ff70462dfb5 UE4Editor-Cmd.exe!FEngineLoop::PreInit() [e:\UE4_WS\engine\source\runtime\launch\private\launchengineloop.cpp:2478]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ff704624b82 UE4Editor-Cmd.exe!GuardedMain() [e:\UE4_WS\engine\source\runtime\launch\private\launch.cpp:135]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ff704624dca UE4Editor-Cmd.exe!GuardedMainWrapper() [e:\UE4_WS\engine\source\runtime\launch\private\windows\launchwindows.cpp:145]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ff704633b4a UE4Editor-Cmd.exe!WinMain() [e:\UE4_WS\engine\source\runtime\launch\private\windows\launchwindows.cpp:276]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ff704634ab6 UE4Editor-Cmd.exe!__scrt_common_main_seh() [d:\agent\_work\2\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ffae07f7974 KERNEL32.DLL!UnknownFunction []
UATHelper: Packaging ():   LogWindows: Error: [Callstack] 0x00007ffae105a271 ntdll.dll!UnknownFunction []
UATHelper: Packaging ():   LogWindows: Error:
UATHelper: Packaging ():   LogWindows: Error: end: stack for UAT