EA Addin - GUI update from a task or a thread

Question

I created an addin in C# and WPF (MVVM). I need to update the GUI after I ran several queries that are taking 8 seconds via repository.SQLQuery(...).

To not block the main thread of the Enterprise Architect, I created a task where to run these queries and at the end I need to update the GUI. The problem is that is not working Application.Current.Dispacher because EA doesn't provide a UI thread dispatcher mechanism.

How can I create a method to no block the main Thread and at the end to update the GUI?

private ICommand _runAsyncButton; 
        public ICommand RunAsyncButton
            => _runAsyncButton ??
               (_runAsyncButton =
                    new DelegateCommand(async p => await ExecuteSomethingAsync()));

 private async Task ExecuteSomethingAsync()
 {
    await Task.Run(() => { 

// taking 8 seconds        
repository.SQLQuery(...)
repository.SQLQuery(...)
repository.SQLQuery(...)

                if (Application.Current.Dispatcher != null)
                    Application.Current.Dispatcher.Invoke(() =>
                    {
                    // code to update the GUI is throwing an exception because Application.Current is null
                    });

     });
 }