My German is pretty dodgy, but I know all the menu words and I'm pretty sure they have a special compartment that routes AC through it for keeping your sausage sammy (wurstbrot) cold. Are there more pictures somewhere?
Their version of the armrest that Tesla supplies is what they call part 3 and it is 670 Euro. The interesting thing is that it screws into the console at the footwell, so it will not wiggle as the Tesla rear console does. On the other hand, it would seemingly be a PITA to remove to fold down the seats. I'm unsure. I'm trying to wade through the forum posts now. I've had to augment my meager skills with Google Translate which combines to let me get about 90% of the conversation.
- - - Updated - - -
Here is a picture of all three rear console pieces at once: