Why is my plugin failing to compile after adding multi-threading in C++

Development Pipeline & Plugins Plugins
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I’ve followed a tutorial that shows how to create a separate thread to run some background tasks within unreal.

I have a plugin that loads a file and the need to parse the file in order to render a 3D object. This locks the UI up so getting this loaded to a separate thread is pretty important.

The Errors that I’m getting are the following

CompilerResultsLog:   [3/6] LoaderBPFunctionLibrary.cpp
CompilerResultsLog:    C:\Program Files\Epic Games\UE_4.25\Engine\Source\Runtime\Core\Public\Async/AsyncWork.h(150) : error C4624: 'FAutoDeleteAsyncTask<LoadTask>': destructor was implicitly defined as deleted
CompilerResultsLog:   C:\Users\Matthew Wallace\Development\Unreal Engine\FulcrumVR\Plugins\FcrmMeshLoader\Source\FcrmMeshLoader\Private\LoaderBPFunctionLibrary.cpp(108): note: see reference to class template instantiation 'FAutoDeleteAsyncTask<LoadTask>' being compiled
CompilerResultsLog:    C:\Program Files\Epic Games\UE_4.25\Engine\Source\Runtime\Core\Public\Async/AsyncWork.h(150) : error C2282: 'FAutoDeleteAsyncTask<LoadTask>::~FAutoDeleteAsyncTask' cannot override 'IQueuedWork::~IQueuedWork'
CompilerResultsLog:   C:\Program Files\Epic Games\UE_4.25\Engine\Source\Runtime\Core\Public\Misc/IQueuedWork.h(40): note: 'IQueuedWork::~IQueuedWork' is not deleted
CompilerResultsLog:    C:\Users\Matthew Wallace\Development\Unreal Engine\FulcrumVR\Plugins\FcrmMeshLoader\Source\FcrmMeshLoader\Private\LoaderBPFunctionLibrary.cpp(116) : error C2248: 'LoadTask::LoadTask': cannot access private member declared in class 'LoadTask'
CompilerResultsLog:   C:\Users\Matthew Wallace\Development\Unreal Engine\FulcrumVR\Plugins\FcrmMeshLoader\Source\FcrmMeshLoader\Public\LoaderBPFunctionLibrary.h(82): note: see declaration of 'LoadTask::LoadTask'
CompilerResultsLog:   C:\Users\Matthew Wallace\Development\Unreal Engine\FulcrumVR\Plugins\FcrmMeshLoader\Source\FcrmMeshLoader\Public\LoaderBPFunctionLibrary.h(79): note: see declaration of 'LoadTask'
CompilerResultsLog:    C:\Users\Matthew Wallace\Development\Unreal Engine\FulcrumVR\Plugins\FcrmMeshLoader\Source\FcrmMeshLoader\Private\LoaderBPFunctionLibrary.cpp(117) : error C2248: 'LoadTask::~LoadTask': cannot access private member declared in class 'LoadTask'
CompilerResultsLog:   C:\Users\Matthew Wallace\Development\Unreal Engine\FulcrumVR\Plugins\FcrmMeshLoader\Source\FcrmMeshLoader\Public\LoaderBPFunctionLibrary.h(98): note: compiler has generated 'LoadTask::~LoadTask' here
CompilerResultsLog:   C:\Users\Matthew Wallace\Development\Unreal Engine\FulcrumVR\Plugins\FcrmMeshLoader\Source\FcrmMeshLoader\Public\LoaderBPFunctionLibrary.h(79): note: see declaration of 'LoadTask'
LogMainFrame: MainFrame: Module compiling took 10.187 seconds
Warning: HotReload failed, recompile failed

Here is what I have thus far.

// Fill out your copyright notice in the Description page of Project Settings.
/// this is the .h 
#pragma once
#include "ProceduralMeshComponent.h"
#include "Async/AsyncWork.h"
#include "Kismet/BlueprintFunctionLibrary.h"
#include "LoaderBPFunctionLibrary.generated.h"

UENUM(BlueprintType)
enum class EPathType : uint8
{
	Absolute,
	Relative
};


USTRUCT(BlueprintType)
struct FMeshInfo
{
	GENERATED_USTRUCT_BODY()

	UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "ReturnedData")
	TArray<FVector> Vertices;

	UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "ReturnedData")
	TArray<int32> Triangles;

	UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "ReturnedData")
	TArray<FVector> Normals;

	UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "ReturnedData")
	TArray<FVector2D> UV0;

	UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "ReturnedData")
	TArray<FLinearColor> VertexColors;

	UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "ReturnedData")
	TArray<FProcMeshTangent> Tangents;

	UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "ReturnedData")
	FTransform RelativeTransform;
};

USTRUCT(BlueprintType)
struct FReturnedData
{
	GENERATED_USTRUCT_BODY()

	UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "ReturnedData")
	bool bSuccess;

	UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "ReturnedData")
	int32 NumMeshes;


	UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "ReturnedData")
	TArray<FMeshInfo> meshInfo;


};

UCLASS()
class FCRMMESHLOADER_API ULoaderBPFunctionLibrary : public UBlueprintFunctionLibrary
{
	GENERATED_BODY()


public:

	UFUNCTION(BlueprintCallable, Category = "MeshLoader")
	static FReturnedData LoadMesh(FString filepath, EPathType type = EPathType::Absolute);

	UFUNCTION(BlueprintCallable, Category = "MeshLoader")
	FReturnedData LoadMeshMainThread(FString filepath, EPathType type = EPathType::Absolute);

};

//////====================================================
class LoadTask : public FNonAbandonableTask
{

	LoadTask(FString _filepath, EPathType _type, FReturnedData _returnedData);

	~LoadTask();

	FORCEINLINE TStatId GetStatId() const
	{
		RETURN_QUICK_DECLARE_CYCLE_STAT(LoadTask, STATGROUP_ThreadPoolAsyncTasks);
	}

	FString filepath;
	EPathType type;
	FReturnedData ReturnedData;
	
	void DoWork();
	void DoWorkMain();

};

.cpp file

// Fill out your copyright notice in the Description page of Project Settings.
#include "LoaderBPFunctionLibrary.h"
#include "FcrmMeshLoader.h"
#include <assimp/Importer.hpp>  // C++ importer interface
#include <assimp/scene.h>       // Output data structure
#include <assimp/postprocess.h> // Post processing flags

void FindMeshInfo(const aiScene* scene, aiNode* node, FReturnedData& result)
{

	
}


void FindMesh(const aiScene* scene, aiNode* node, FReturnedData& retdata)
{

}



FReturnedData ULoaderBPFunctionLibrary::LoadMesh(FString filepath, EPathType type)
{
	FReturnedData _returnedData;
	(new FAutoDeleteAsyncTask<LoadTask>(filepath, type, _returnedData))->StartBackgroundTask();
	return _returnedData;
};

FReturnedData ULoaderBPFunctionLibrary::LoadMeshMainThread(FString filepath, EPathType type)
{
	FReturnedData _returnedData;
	//LoadTask::LoadTask* task = new LoadTask(filepath, type, _returnedData);
	LoadTask* task = new LoadTask(filepath, type, _returnedData);
	delete task;
	return _returnedData;
};

//==============================================================
LoadTask::LoadTask(FString _filepath, EPathType _type, FReturnedData _returnedData)
{
	filepath = _filepath;
	type = _type;
	ReturnedData = _returnedData;
}

LoadTask::~LoadTask()
{
	UE_LOG(LogTemp, Warning, TEXT("Mesh Finished Loading"));
}

void LoadTask::DoWork()
{
	
}

void LoadTask::DoWorkMain()
{
	DoWork();
}