Please note that the Send() method only sends data.
To display changes on the terminal screen, you have to process incoming data, typically by calling one of scripting.ReadUntil(), scripting.WaitFor(), scripting.Process() methods.
Also please note, that you have to call terminal.Screen.GetRegionText() every time you want to get updated data.
If you are in doubt, please create communication log to see what is going on:
client.LogWriter = new FileLogWriter("c:/data/telnet.log", LogLevel.Debug);