Pass MWNumericArray from c# DLL to MATLAB function

I have some c# code and compiled them to x64 DLL to be used in MATLAB 2017a. The MWArray.dll I am using is the same version as 2017a. I am using .NET framework 4.6.1.

Here are my c# code:

using MathWorks.MATLAB.NET.Arrays;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MATLABarrayTest
{
    public class Data
    {
        public static int[] GetData1()
        {
            return new int[] { 555, 666 };
        }
        public static MWNumericArray GetData2()
        {
            return new int[] { 555, 666 };
        }
    }
}

Here are my MATLAB code dotnetdlltest.m:

clear
clc
dllpath  = 'C:\Path\to\MATLABarrayTest\bin\x64\Debug\MATLABarrayTest.dll';
asmInfo  = NET.addAssembly(dllpath);
data = MATLABarrayTest.Data.GetData1;

This works fine and returns a 1X1 Int32[] data object and I can access the data like:

>> data(2)

ans =

  int32

   666

However, if I call the GetData2() function as:

clear
clc
dllpath  = 'C:\Path\to\MATLABarrayTest\bin\x64\Debug\MATLABarrayTest.dll';
asmInfo  = NET.addAssembly(dllpath);
data = MATLABarrayTest.Data.GetData2;

I get the following error message:

Error using dotnetdlltest (line 5)

Message: The type initializer for 'MathWorks.MATLAB.NET.Arrays.MWNumericArray' threw an exception.

Source: MWArray

HelpLink:

I am wondering why the return type MWNumericArray would throw such an error message?

When GetData1() return an object, I was not able to view the data in this object as a table in MATLAB like an array, so I am trying to figure out a way to view it as an array. Is that something possible to do?

Thank you very much for the help!