"Is the default configuration of grub.cfg on the flash chip supposed to
automatically look for libreboot_grub?"
Yes. This is what I've been trying to explain. :)
https://libreboot.org/docs/gnulinux/grub_cbfs.html has "by default, GRUB in
libreboot is configured to scan all partitions on the main storage for
/boot/grub/libreboot_grub.cfg or /grub/libreboot_grub.cfg(for systems where
/boot is on a dedicated partition), and then use it automatically."
The key point there is "and then use it automatically." :)
