Last update, I got it to work, so here are a few pointers for the next one reading this. The issue is that I edited armbianEnv.txt correctly, but somehow the dtb file was missing (most likely due to being merged with the one in use, despite this work being WIP and not working for the emmc/wifi). I read a little about dts/dtb, this is a good resource, but TLDR dts stands for device tree source and dtb for device tree blob. The former compiles into the latter, and armbianEnv.txt wants the blob, not the source (could compile on demand? who am I to judge). The dts for the 5b is somewhere out there to be compiled into the dtb, but since I knew I had the orangePI debian working, I searched for the dtb there first, and found it. I copied is over to a freshly compiled image, pointed the boot record to it, and was able to make it all work. Here are a few commands.
I first mounted `Orangepi5_1.1.4_debian_bullseye_desktop_kde-plasma_linux5.10.110.img` on my own machine (not the pi):
fdisk -l /media/data/projects/2023/orangepi/images/Orangepi5_1.1.4_debian_bullseye_desktop_kde-plasma_linux5.10.110.img
# 512B block size * partition 1 located at 61440=31457280
sudo mount -o loop,offset=31457280 /media/data/projects/2023/orangepi/images/Orangepi5_1.1.4_debian_bullseye_desktop_kde-plasma_linux5.10.110.img /media/cdrom
cp /media/cdrom/dtb-5.10.110-rockchip-rk3588/rockchip/rk3588s-orangepi-5b.dtb /tmp/
Now we have extracted the file.
Then boot up `Armbian_23.5.0-trunk.140_Orangepi5_lunar_legacy_5.10.110_xfce_desktop.img` on the pi and and scp the blob there:
scp /tmp/rk3588s-orangepi-5b.dtb root@192.168.1.14:/boot/dbt/rockchip/
then edit `/boot/armbianEnv/txt` to have this line:
ftdfile=rockchip/rk3588s-orangepi-5b.dtb
reboot, you should see the emmc. On to install this system to it.
Installed gparted, deleted everything from the emmc and formatted it to ext4.
Then run `nand-sata-install` and chose the option `boot+system on emmc`, let it finish, quick `sync;poweroff`, then unplug the power cord, remove the sd card, plug the cord it back, it boots 😎