Having different plots while using parfor loops for MATLAB Simulink

I am trying to a parameter sweep of a model using parfor, but I can see from the plots of the results that they are different from the actual simulation results. However, when I replace parfor with for, the results match up. I am clueless as to why this is happening. Any help would be appreciated.

My code:

% 1) Load model and initialize the pool.
model = 'real_mismatch_model';
load_system(model);
matlabpool('open');

% 2) Set up the iterations that we want to compute.
RMS_sweep = [6 18 30]; 
iterations          = length(RMS_sweep);
simout(iterations)  = Simulink.SimulationOutput;

% 3) Need to switch all workers to a separate tempdir in case 
% any code is generated for instance for StateFlow, or any other 
% file artifacts are  created by the model.

spmd
    % Setup tempdir and cd into it
    addpath(pwd);
    currDir = pwd;
    addpath(currDir);
    tmpDir = tempname;
    mkdir(tmpDir);
    cd(tmpDir);
    % Load the model on the worker
    load_system(model);
end

% 4) Loop over the number of iterations and perform the
% computation for different parameter values.
parfor idx=1:iterations    
    set_param('real_mismatch_model/PCC values/RMS2','Freq',num2str(RMS_sweep(idx)));

      simout(idx) = sim(model, 'SimulationMode', 'normal');
  end

% 5) Switch all of the workers back to their original folder.
spmd
    cd(currDir);
    rmdir(tmpDir,'s');
    rmpath(currDir);
end

close_system(model);
matlabpool('close');