$100 Billion may sound like a lot to you but that doesn't mean it's meaningful in regards to the actual damages done. More often than not when massive horrible things are done by Corporations (the crash of the financial/real estate markets, the Gulf oil spill, etc.) large corps get hit with penalties that look massive to an individual but actually only represent a small part of the true cost of restitution and only represent a day or two of operating profits at most for the company.
What happened in the story is so astonishingly unjustly inverted from that scenario because, in contrast, this guy was hit with the entire cost of the damages (even though he was only a tiny contributor to the actual crime, and that penalty probably represents many years worth of profits for him (minus the basic costs of living and taxes). It would be like fining JP Morgan all the Trillions of dollars that were estimated to have been lost throughout the economy because the courts didn't feel that they were likely to be able to clearly identify any of the other big players in the crime. Then, for good measure, make it so that the costs of litigating appeals of that verdict would be so expensive that it was guaranteed to drive the company into complete bankrupts (since even if this guy has a decent job and was able to afford a non-state appointed attorney for this trial it's unlikely he'll be able to hire a highly competent set of lawyers throughout the entire appeals process in the same way major companies to in order to successfully drive down the original, already too small, fines they are hit with).