Execute SSIS (package) in SSMS using T-SQL and return a value

Using VS (2019) I created an Integration Services Project to code an SSIS package. The goal was to call a Web API from an SSIS package using input variables like username/password/url and so on. I successfully achieved this using Script Task and Dts.Variables and F5/Run to see successful results. What I want to achieve now is to return (like an out parameter) an Id returned to me by the Web API. I want to have this Id returned in the SSMS Results window when I execute the SSIS script in SSMS.

Here is what I have done:

1. VS > Open dtsx file in Designer and in the "Control Flow" tab, right clicked to add variable:

2. Right clicked the Script Task I had created and added the variable created above in the ReadWriteVariables section:

3. Using "Edit Script" to code the Web API call and return a value and set it as follows:

   //MessageBox.Show(id);
   Dts.Variables["User::Id"].Value = Convert.ToInt32(id);

The MessageBox was just to test if the id is returned by the Web API and I get an alert of the "id" when I Run/F5 the SSIS project in Visual Studio. The second line is where I have set the Variable.

4. I execute the SSIS in using T-SQL in SSMS from an example here:

   Declare @execution_id bigint

   EXEC [SSISDB].[catalog].[create_execution] @package_name=N'ssisWAP.dtsx', @execution_id=@execution_id OUTPUT, @folder_name=N'SSIFolder', @project_name=N'SampleProject', @use32bitruntime=False, @reference_id=Null

   Select @execution_id

   DECLARE @var0 sql_variant = N'username'

   EXEC [SSISDB].[catalog].[set_execution_parameter_value] @execution_id, @object_type=20, @parameter_name=N'Username', @parameter_value=@var0

   DECLARE @var1 sql_variant = N'password'

   EXEC [SSISDB].[catalog].[set_execution_parameter_value] @execution_id, @object_type=20, @parameter_name=N'Password', @parameter_value=@var1

   EXEC [SSISDB].[catalog].[start_execution] @execution_id

The above executes properly, calling the API and an out @execution_id is shown in Result window. But no sign of the variables User::Id I created earlier. Is it possible to show that value in the Result window? If not, is there a way to see that the data in that variable in SSMS after SSIS execution (even from designer)?

I already had a look at this post: Returning Output Paramters or Variables From SSIS Script Task / Script Component

where the solution is to use "Execute SQL Task" and "pass" the variable into a procedure. This I guess is one way to do it but I want to just get the Id in the return when I execute the script as shown above.

Any help will be appreciated. Thanks