Hi,
The Discovery method takes 2 parameters: the first one is Timeout - used for limit time for discovering procedure (default value is 30 seconds). The second one if Fast The default value is "False" which means execute full discovering. If you set this second "Fast" parameter to "True" then the Discovery method returns only already paired devices.
Once you get this list (it executes fast) you can call wclBluetoothDevice.GetConnected() method which returns "True" through its "Value" parameter if the device is connected.