How to pass an object of LinearModel Class as output to a .Net Interface ?

I have a function that i am compiling using Matlab Compiler (to create a DLL for .Net Assembly). The function uses the input and develops a Linear model using stepwise regression. Here is the code

function [Rsq,Mdl] = DevelopModels(Input,Output)
Mdl = LinearModel.stepwise(Input,Output,'linear','verbose',0);
Rsq = Mdl.Rsquared.Ordinary ;
end

I then compile this function using Matlab compiler into a DLL for .Net Assembly. Here is the code in C#

CollectData cd = new CollectData();
        int[,] designSamples = new int[,]
        {
            { 0,   10  ,5   ,150},
            { 0 ,  205,25  ,125 },
            { 0   ,400 ,5  , 100 },
            { 50  ,10  ,15 , 100 },
            { 50  ,400 ,25 , 150 },
            { 100 ,10  ,25 , 150 },
            { 100 ,205 ,15 , 150 },
            { 100 ,400 ,5  , 125 },
            { 100 ,400 ,25 , 100 },
            { 100 ,10  ,5  , 100 },
        };

          int[] exampleRankings = new int[]
          {
              2      ,
              3      ,
              6      ,
              4      ,
              7      ,
              6      ,
              5      ,
              8      ,
              8      ,
              5
          };
          MWNumericArray designSamplesMW = new MWNumericArray(designSamples);
          MWNumericArray rankingsMW = new MWNumericArray(exampleRankings); 
          MWArray[] models = cd.DevelopModels(2, designSamplesMW, rankingsMW);

On the .Net side when i try to use this DLL, i get proper values in Rsq but Mdl is returned as NULL. What am i doing wrong ? Can i not return mdl as output to .NET ?