UE5.3 Standalone Crashed - Array related - Works fine in PIE

Development Programming & Scripting
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Following my previous post (only the edited part is relevant), someone suggested me to install the Editor Symbols - Debugging tools to get the Call Stack of the error.
This is the full error that came. The starting part is still same, related to some Array but the remaining one is very cryptic to me. It has something to do with GPU that’s for sure but what Plugin/Setting is it?

Any help is appreciated. Thanks.

Assertion failed: (Index >= 0) & (Index < ArrayNum) [File:D:\build++UE5\Sync\Engine\Source\Runtime\Core\Public\Containers\Array.h] [Line: 771] Array index out of bounds: -1 from an array of size 4

UnrealEditor_Engine!FGPUSkinCache::EndBatchDispatch() [D:\build++UE5\Sync\Engine\Source\Runtime\Engine\Private\GPUSkinCache.cpp:1897]
UnrealEditor_Engine!EndSendEndOfFrameUpdatesDrawEvent'::2'::<lambda_1>::operator()() [D:\build++UE5\Sync\Engine\Source\Runtime\Engine\Private\LevelTick.cpp:1006]
UnrealEditor_Engine!TEnqueueUniqueRenderCommandType<EndSendEndOfFrameUpdatesDrawEvent'::2'::EndDrawEventCommandName,EndSendEndOfFrameUpdatesDrawEvent'::2'::<lambda_1> >::DoTask() [D:\build++UE5\Sync\Engine\Source\Runtime\RenderCore\Public\RenderingThread.h:209]
UnrealEditor_Engine!TGraphTask<TEnqueueUniqueRenderCommandType<EndSendEndOfFrameUpdatesDrawEvent'::2'::EndDrawEventCommandName,EndSendEndOfFrameUpdatesDrawEvent'::2'::<lambda_1> > >::ExecuteTask() [D:\build++UE5\Sync\Engine\Source\Runtime\Core\Public\Async\TaskGraphInterfaces.h:1265]
UnrealEditor_Core!FNamedTaskThread::ProcessTasksNamedThread() [D:\build++UE5\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:758]
UnrealEditor_Core!FNamedTaskThread::ProcessTasksUntilQuit() [D:\build++UE5\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:649]
UnrealEditor_RenderCore!RenderingThreadMain() [D:\build++UE5\Sync\Engine\Source\Runtime\RenderCore\Private\RenderingThread.cpp:411]
UnrealEditor_RenderCore!FRenderingThread::Run() [D:\build++UE5\Sync\Engine\Source\Runtime\RenderCore\Private\RenderingThread.cpp:537]
UnrealEditor_Core!FRunnableThreadWin::Run() [D:\build++UE5\Sync\Engine\Source\Runtime\Core\Private\Windows\WindowsRunnableThread.cpp:149]
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**Edit - FIXED ! - Learned from the editor debugging tools, that it was somehow related to GPU Skin Cache. And also, from my other post, it was evident that it was centered around my main PlayerBP’s Char Mesh.

Replacing the Pawn from my Char to Default Manny UE5 TP Char resulted in no crash. What I then did, was to delete all SK Mesh components and run the player naked. Which worked, that means the meshes have somehow corrupted their skin cache (given that is the top most error in the stack). Then, I removed all parts of the Metahuman (face, feet, torso, and legs) leaving only the body mesh, and it crashed. I removed the Body Mesh and set it to none, IT DID NOT CRASH !**

This simply proved the theory that it indeed was the Body Skeletal Mesh. It works when all Components are there EXCEPT the body mesh of this Metahuman. Okay so how I solved it? I slowly chipped away all the details and it came down to 2 things. Ray Tracing Support being enabled, and GPU Skin Cache being Enabled on Body Skeletal Mesh, somehow both fighting for something.

Ran tests with each of them toggled On/Off one by one and it turns out, it has to be a bug or something, but with Ray Tracing Enabled, it’s crashing no matter you turn SkinCache enabled or disabled. Turning RT off in Project settings fixes this. After which you can enable or disable skin cache (which is useless as skin cache depends on RT being enabled). Idk, I’m not a backend Engineer for Unreal but this makes no sense to me. It never used to crash and now it is crashing even though I had RT enabled from the beginning. For me it’s not that big of a deal as it’s my first game and I don’t have highly reflective surfaces to utilise RT and software shadows look good already with Lumen GI.