Different behaviour when using a command line script or running it from a backgroundworker

I have a really weird problem which recquire a strong knowledge of C# 's backgroundworker.

I want to run a command line program and check its ERRORLEVEL.

cmd.exe /c echo Launching the command && COMMAND_TO_RUN & echo Connexion statut : && echo %ERRORLEVEL% && if %ERRORLEVEL% NEQ 0 (echo FAILURE) ELSE (echo SUCCESS))

When the command fail, the ERRORLEVEL get the value -1

This works when I use this line in the cmd.exe.

But, here is the problem.

When I use a background worker to run this line, the ERRORLEVEL take the value 0 even if the COMMAND_TO_RUN fail.

Here is my backgroundworker code :

string[] args = { "/c echo Launching the command && COMMAND_TO_RUN  & echo Connexion statut : && echo %ERRORLEVEL% && if %ERRORLEVEL% NEQ 0 (echo FAILURE) ELSE (echo SUCCESS))};
backgroundWorker1.RunWorkerAsync(args);


 private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
    {
        string[] args = e.Argument as string[];
        System.Diagnostics.Process process = new System.Diagnostics.Process();
        process.StartInfo.UseShellExecute = false;
        process.StartInfo.FileName = "cmd.exe";
        process.StartInfo.Arguments = args[0];
        process.StartInfo.CreateNoWindow = true;
        process.StartInfo.RedirectStandardInput = false;
        process.StartInfo.RedirectStandardOutput = true;
        process.StartInfo.RedirectStandardError = false;
        process.Start();
        System.IO.StreamReader sOut = process.StandardOutput;

        string tempOut;
        while (!sOut.EndOfStream)
        {
            // using the report progress userstate allow me to catch 
            // the program output in runtime
            tempOut = sOut.ReadLine();
            backgroundWorker1.ReportProgress(1, tempOut);
        }
        process.Close();
    }

So Does the use of a backgroundworker lead to a particular value of the ERRORLEVEL ?

Thanks in advance