Sounds like risk management. I presume he wants to stay married but also wants to protect his business ventures by getting her to agree to a maximum payout. I've known many wealthy men who were completely financially destroyed by divorce. There is often no clean way of splitting a business and having to liquidate cash to buy the partner out can often sink the company.

On a related note, I consider Amber Heard as a risk to the whole Mars mission and get a bit nervous when I hear rumors of them getting back together. I wonder if I'm the only one.

Edit: I grew up in farming country and by far the biggest risk to farms there is divorce. This is insane given all of the other risks in farming.