Volkswagen Passat B5 - connecting an additional USB socket for the lighter

Hello, I have a VW Passat B5 from 2000. In the middle of the dashboard I have 1 lighter socket, unfortunately when traveling further, turning on the video recorder as well as some navigation or yanosik in the phone begins the problem with a small number of charging inputs. The video recorder occupies the cigarette lighter socket so there is nothing to connect the phone to. At the beginning I thought about the cigarette lighter socket but something is already sticking out, it is big and tangled up. Recently, I came up with the idea to mount something like this: I would like to mount such two on both sides of the center console at the gear stick. I will easily hook up the telephone and video recorder to one, and the other will stay in the case of the phone, e.g. of a passenger. Then the cigarette lighter socket will not be used.

Due to the fact that the cables go to the lighter and will be the least undressing connecting these USB sockets just to them I wanted to mount them under those already going. I dismantled the lighter today, thinking I would find only two cables and I was a bit surprised.

Can you tell me which cables to mount these new USB sockets for? Ew. how can i check it? I am sending photos as currently I have a lighter connected.

I think that the use of such sockets will be the most aesthetic solution and the simplest. However, if any of you have any other idea, I would love to hear it. Thank you in advance for your help.

I quote from the classic: "Plus and minus are the only things I see. Plus and minus are the only things I live"
So without metamorphoses and this one. Measuring the feet and measuring, measuring

You know what, I'm totally beginner when it comes to any mechanics in the car. Recently, I replaced the turn signal light bulb myself and connected a new 2din radio and I consider it a success. And a meter (multimeter) I just want to buy first in my life and I'm looking for something myself, not knowing what to choose. I guess the two cables are + and - and probably the next one is backlight? which doesn't work for me (I don't know why).

Brown minus; red plus; blue plus backlight - surely the bulb is burnt off ?

And three more questions in the subject.
1. When the video recorder is connected to the cigarette lighter socket, it works even after removing the key from the ignition.
2.related to the first, so that these USB sockets work only after inserting the key to the ignition switch to connect to the brown cable - minus, and blue from the backlight? do I have to connect to the brown and red and each time manually disconnect the video recorder so far?
3. Why are the blue cables from the backlight two?

1 This is because the electricity is still in the socket
2 you can not connect to the backlight because there is probably a current through the dimmer so there is a risk of trusting it. If you want to turn off the power to the sockets with the key, you need to look for a "plus".
3 two because the current comes in to shine in the socket and the other goes out to illuminate somewhere else. They are connected together in one connector.

Thank you, so I won't play searching + after the ignition because I think it's too hard for me now. So I plug cables to connectors brown and red because it will be the simplest. Thank you.

Plus after the ignition should be in the radio connector.

In fact, in total, as the radio came and connected the ISO cubes as they were originally, each time the key was removed from the ignition switch the radio deleted. I had to change two wires in the cubes (probably black with blue, i.e. the one from the support and voltage after turning the key on) and then it started to work properly. So all in all I could connect to it.