The Libreboot documentation located here provides some really good information for helping you installing your Linux distro. Before I flashed my laptop I had installed Ubuntu to test everything and make sure it worked well. After I finished flashing it I tested various things like sleep and booting from my tails USB drive. Next it was time to install Debian on the primary hard drive.
Booting ISOLINUX images (manual method)
For whatever reason my tails flash drive booted with no problems using Parse ISOLINUX menu (USB) but the Debian flash drive only loaded the background and would not boot. After looking again at the documentation I found the manual method.
These are the commands I had to run for my Debian 8.2 AMD64 USB drive:
linux /install.amd/vmlinuz vga=788
I used an encrypted LVM partition layout during the installation. An interesting thing about Libreboot is it uses a GRUB payload built into the firmware. Therefore when you tell your installation to setup the GRUB boot record that information is basically ignored.
Again… they have more information to help you through this! http://libreboot.org/docs/gnulinux/grub_cbfs.html
I have been pretty impressed by their documentation and it has had information about all the things I have run into along the way. Of course it is not specific information regarding my linux distribution but it is fairly easy to figure out from what they have provided and then people like me can publish stuff for those who are a little newer to linux.
Search for GRUB configuration (grub.cfg) outside of CBFS
This option worked for me to boot Debian. At first I had planned on updating the GRUB payload in the firmware. I started working on that process and later decided it was a lot of hassle. For one, if I decide to update to a newer Libreboot release I will have to do this over again along with switching out the MAC address. Two, if I decide to install another Operating System the configurations may not match.
Another option was to add a symlink called libreboot_grub.cfg which points to the installed grub.cfg. It is important for this to be a symlink instead of a copy because this file can change during upgrades.
$ cd /boot/grub/
$ ln -s grub.cfg libreboot_grub.cfg
This is what I ended up doing. Simple, quick, effective.