@millihertz
> 32-bit EFI as the only boot environment
I think this is what's making this configuration rather exotic, I doubt that it gets enough testing. I'd try booting it in recovery mode and running udev manually to see what prevents it from proceeding.
If it can't boot even into recovery mode, try giving it an invalid root partition, this should make it give you a shell with only initrd mounted.
@m0xee it didn't even boot into recovery, but following a random tip on reddit, i added a 20s timeout to udevadm settle, and apparently that's all it needed... weird