Digging in further, the bootloader module fails because it depends on the partition module. However, there isn't a partition module in: /usr/lib/x86_64-linux-gnu/calamares/modules
I also created a chroot for x86 and /usr/lib/i386-linux-gnu/calamares/modules doesn't have the partition module either. I suspect this is the root of the issue but I am seeing if I can confirm.
