Hello, I'm Danny.
Here are the radio wiring diagrams you requested. I've attached the pictures below for both audio systems available on your VW- (Monsoon and Non-Monsoon). I've cut the pictures into 3 pieces so you can view larger. In the last 2 pictures I've circled the pin 5 and 7 circuit you mentioned in blue. Hope this helps and thanks for using 2CarPros.
Images (Click to enlarge)
Friday, May 7th, 2021 AT 9:19 PM