A hundred terabytes is a lot of information, but I don't think it would take too long to download. Another way to look at is like this...it's roughly 100,000 gb. If I split that amongst different systems I grant access (let's say 20), each system is responsible for downloading 500 gb. If I, your average joe, can download a 40gb file in a couple hours on a shitty ISP plan, then surely each system could download 500gb in half a day.
Then again, what the **** do I know?
I hope it was an inside job.