How do i fix brightness and external monitors? (Latitude 7480)

Hi guys,

So after struggling around for the last few days i've managed to make almost everything work.

I still need to fix brightness controls and external monitors. as per the brightness issue - it just won't work. if i move the sliders almost all the way down it still stays the highest, and when it's on the lowest screen goes full dark.

Regarding the monitors, I'm using a Dell WD15 USB-C 180W docking. I have 2 external monitors connected to it (mini DP and HDMI). Laptop is one screen and then it uses the other external screens as a duplicate screen (not of the laptop, but as an another one screen). (a diagram for explanation)

I'll be very grateful if anyone can help me solving this.

Attaching my EFI folder.

I'm running on Catalina 10.15.2 btw.

Have a nice weekend!