1st photo.
Not sure at what stage you took this photo but is that how the WHT/BLU wire connected to the centre terminal of the cigarette lighter socket?
Can't remember exactly but it should be covered in high temperature spec connector housing (possibly in custard cream colour) with specific terminal design.
I think your photo is showing the remains of this special design without the connector housing.
Because the photo was taken after pulling the centre console off and due to the angle of the photo, can't really tell but if there was no insulation around the terminal,
it could easily short to the GND when you wiggled the splitter in your post
#1 , under vibration, etc or simply the last time when the centre console was re-installed.
The fuse could be blown as soon as you turned the IGSW into P2 ACC even before trying to power up any devices connected.
If you are going to insulate it, please use high temperature spec material.
You may not smoke or never uses the lighter but in case someone actually uses the real cigarette lighter in the future.
Kaz