Hi @Ben93kie,
thanks for still following up with us though its a seemingly painful process. And I totally understand the possible pivot.
It took me a bit to follow up because I really wanted to give it a good inspection instead of just saying “sorry”. So if my understanding is correct, then the magic lies in this file: balena-jetson-orin/layers/meta-balena-jetson/recipes-kernel/linux/linux-jammy-nvidia-tegra/tegra234-j401-p3768-0000+p3767-0000-recomputer.dtb at master · balena-os/balena-jetson-orin · GitHub as appended here: balena-jetson-orin/layers/meta-balena-jetson/recipes-kernel/linux/jetson-dtbs.bb at 91389bfdd0221457a9250532adafd4ee733674a2 · balena-os/balena-jetson-orin · GitHub. The install logic is in balena-jetson-orin/layers/meta-balena-jetson/recipes-kernel/linux/jetson-dtbs.bb at 91389bfdd0221457a9250532adafd4ee733674a2 · balena-os/balena-jetson-orin · GitHub, and that also gives away that balena extracted from GitHub - Seeed-Studio/Linux_for_Tegra: Seeed Jetson reComputer && reServer default Image source code.🎁 🎁 🎁 - commit 5b18d7990ca342bbeb70ce5715ea0473d118278f, branch r36.4.3 
So in a nutshell, my final suggestion would be to give that a spin. How to inject a DTB properly in meta-tegra, maybe @graceagrace or @dwalkes can give you some assistance.
Really hope we can figure this out, and if not then thanks a lot for all your effort. And of course, you know where to find me.
Greetz,
Josef