I do not know of a way to suppress the Send/Retrieve dialog.
You may wish to experiment with recording in an applet the steps taken by GroupWise itself in Remote mode, as follows.
- Go to Applets on the GroupWise main menu, and select Start Recording.
- Send a test message via the GroupWise user interface.
- Go to Applets on the GroupWise main menu, and select Stop Recording.
The recorded applet may expose GroupWise Object or Token API methods that you need for Remote mode.
I hope this helps.