I had mine upgraded at the dealership back when I first bought my 2015 CLA. I didn't bother to try to get the part itself, as it had to be ordered from Mercedes Germany. Plus there was also some software programming and updating required. Too much hassle to try to DIY.
The video shows NTG 5.x and you have NTG 4.x. Some people have had luck in the past with a blue OBD dongle, but pretty sure it has to be in a specific range for manufacture date. Discussion around this was a lot more frequent a few years ago when the 2015’s were the newest & first gen, so you might have luck with the search bar. If you get a dongle and it brick’s your head unit I take no liability lol.
