[Libreboot] Is it impossible to boot distros other than Trisquel GNU/Linux on a Libreboot X60 or is something broken on my machine?

[bard]

I want to keep Trisquel GNU/Linux on my Libreboot X60 forever, I don't plan on replacing it. However for certain tasks I have to boot other distros on my machines, and it seems that on my Libreboot machine it refuses to boot anything other than Trisquel. I've tried Byzantium, Tails, Ubunbu GNOME, RLSD, and Xbuntu, and they all give the same error.

Upon booting it the first time, I am greeted by this:
https://i.imgur.com/gUlcCC8.jpg

If I go back to the main menu and try again, I get this:
https://i.imgur.com/LXYKAJ8.jpg

It is exactly the same with all of them except for Trisquel. That works just fine, no problems. And I write the .ISO file to the thumbdrive the exact same way I do all the others, with dd.

So I'm stumped. I'm lost. I'm not sure this is the right place to ask this. Could someone help me please?