@iska You won't see anything in grub's console, as grub is no longer running when Linux is launched.
He mentioned that Linux booted, and stuff about networking, which strongly implied that the login prompt worked, but of course he didn't actually say what occurred.
Linux does output logs to framebuffer during early boot and so you can boot up just Linux (with no rootfs) and watch it panic(), but it's a incredible stretch to say the computer can "boot linux" - when booting didn't finish.