As Fred said, yes it doesn't have to be the official VW stick, you can use any generic USB WI-FI dongle. I used an EE one for a short while but then when Fred directed me towards the super Macrodroid app for Android, I've totally automated the process of enabling and disabling my Wi-Fi hotspot on my Galaxy S7 (now Galaxy S9)
As soon as my phone connects to my named in-car Bluetooth system, it automatically starts the WI-FI hotspot, and when I turn the car off and my car Bluetooth shuts down, MacroDroid automatically disables the WI-FI Hotspot.
It works so well, i don't bother with the car stick at all now.