That is for the company to stay in business. They call it the cost of doing business.
Now here is a ponderable: Let's say YOU are a billionaire, and one country (where you don't intend to live at all) wants you to spend a few months in prison. Would you do it?
I think they offered him a deal what he couldn't refuse. They probably told him to take the deal and pay the business and personal fines (and give the customers' data up), rather than being put on the terrorist list and being hunted for the next few decades, while the company goes out of business. I wonder if they give him immunity from further charges. If not, he may stay for a while in the USA.
Few months? What's the point of that? US Govt gonna sentence him, it's gotta be a few years. Dude needs Steve Cohen's lawyers to help him out.