most Chromebooks can run Linux by writing by writing over a sector of the ROM. Most (and probably this laptop) unfortunately can only write to the RW_LEGACY or BOOT_STUB which introduce significant problems. I'd definitely just run crouton for these.
https://johnlewis.ie/custom-chromebook-firmware/rom-download...
It requires opening the machine though (and then turning a screw), both as a crude security measure (it's not a drive-by attack if it takes 10 minutes of physical access) and a stability guarantee (without the modification, the system basically can't be stuck, no matter how broken an update might be).
Disclosure: I work on Chrome OS firmware.
https://wiki.archlinux.org/index.php/Chrome_OS_devices/Chrom...
Along with the link above indicates otherwise. Are these websites both wrong?
I did completely overwrite the firmware for my Acer c720 (by removing that write protect screw) but I assumed that was an exception.