Hands and feet are time consuming to render compared to a femur I would assume. The fact that I've also looked at those skeletons at least a few times and never noticed, in a way justifies the shortcuts. However I like your theory.... Obviously the information contained within the archive is important, we know there is stuff in there about the black garden, probably much more, seemingly untapped until ghost gets in.... So I imagine the Fallen (who obviously still have access through back and side doors that guardians do not, tortured the scientists trying to get them to open the archive, which they were either unable or unwilling to do. Given that [i]all[/i] Fallen dregs themselves practice voluntary [b]self-amputations[/b] on their lower set of arms as a sign of loyalty and subservience to their leaders, I'm sure they are more than comfortable performing the grisly act on humans who may hold valuable information. I'm actually starting to think the ridiculously ambiguous storyline isn't such a bad thing because it leaves room for speculation such as this which can be very entertaining.