Since I haven't encountered an Xbox with that late of a manufacturing date, I can't offer anything more than speculation.
What you're describing sounds like Linux isn't able to mount the filesystems on the hard drive... If you're feeling adventurous, you could try using the 007AUF exploit to run EvoX, backup the Xbox to your computer, reformat the Xbox's hard drive, then reload it. (Course, this assumes EvoX doesn't just call some APIs in the kernel to recreate the filesystem exactly the way it was. I'm not sure how EvoX's format routine works on the low-level.) Be warned though, IF MS did change something about the drive's partitions/filesystem, there's a chance the retail BIOS may no longer boot or even be able to read from the reformatted drive (if for example, MS made some change to FATX).
I think if it were me, I'd use 007AUF/EvoX to find out the hard drive's lock code, and lock a spare drive with it and futz around with THAT drive instead, while the original Xbox's hard drive is safely tucked away. <