Hi,
I'm keen to hear how it's going with your issue? I enjoyed reading your story of frustration, haha. Anyway, I had the same problem and I think I might have found a fix. It turned out my headset was in Bluetooth mode. As soon as I switched to wireless mode, it connected with the dongle. Here are the instructions I followed to switch mode:
BLUETOOTH MODE
With the headset powered on, enable pairing by holding the MFB until the status LED rapid blinks red and blue. When the headset is paired, the status LED will blink blue. Quick press the power button to toggle between RF wireless and Bluetooth modes. When the headset is in RF wireless mode the status LED will blink red, orange or green depending on the current battery level. Note when the headset is in RF wireless mode and paired via Bluetooth with a mobile phone, it will only accept and receive phone calls. Quick press the power button to enter Bluetooth mode and enable both phone calls and Bluetooth audio (such as when listening to music). The headset will default to the last mode it was set to when turned off.
Hope it helps!