BliteKnight

For anyone coming to this post facing the same issue - I solved my problem.
 
Following the guide here: https://forum.inovato.com/post/building-armbian-from-source-12449428?pid=1333459893
 
I was able to build the latest from trunk - Armbian_23.02.0-trunk_Aw-h6-tv_bullseye_current_5.15.91 which I was able to boot from an SD card and then write to the boards emmc
The guide applies some patches to the build process - one of which is an emmc patch, which I'm going to assume fixed the issue.
 
It took 4+ hrs to build the image on a single core linux VM, so if you are going to attempt this just know it will take that long to make the image.