You need to speak with Libreria Oracle to determine whether it support the macOS iODBC Driver Manager.
How did you configure the DSN did you edit the odbc.ini file manually or does it have a loadable Setup Dialog for the driver ?
When you click the Test DSN button the driver should load a login dialog if implemented, which given you indicate a blank window appears it would appear it does not. It maybe that driver does not implement the GUI dialogs for use with GUI apps and has to be manually configured and connect manually to application with connect string params passed as a string and not via a GUI login dialog.
If you want a working Oracle ODBC Driver that support iODBC on macOS then our drivers does, but is a licensed driver as that is our line of business …