128i E88 Logic 7 head unit

[Jasonrs4]

Hi all.
I’ve got a 2011 128i E88 Sport package with the logic 7 harman Kardon audio. No I drive display.
I have looked for a while trying to find a head unit for an upgrade.
I decided to go with the xtrons ICE/HU/QFB1087UN_L. It says is has everything I’m looking for and most importantly it says it will work with my factory audio system fiber optic.
This unit requires you to cut the dash to get the monitor to mount so before doing this I just plugged everything in to see how it works first.
First problem I had was no audio.
The fix was moving the fiber optic from the factory harness to the supplied one.
Now I have sound from the factory head unit but still no audio from the xtrons.
After a few emails with xtrons they asked me to use the supplied aux stereo cable and run it from the xtrons audio out to the aux in under my armrest. Ok so now I have audio from the xtrons.
Problem is that is a stupid solution for something and it is only stereo audio .

Question to any of you.
Do you think I’m missing something like a wire swap in the harness of who knows.
Another question.
Is there a head unit that will connect to my factory logic 7 fiber optic seamlessly.
The only caveat being that most of the units I’ve seen require you to loose the power top or lower most buttons and I don’t want to do that.

I did go to a shop originally to seal out a head unit but the over $2000 price lead me in this direction.
I have installed many stereos and used to do installs as a side hustle but it’s been a while and this just is just aggravating.

Thanks for any help