This sounds like a good idea but getting the checkbook out at a company like Microsoft probably takes 3-5 meetings, and saying you want to donate because you accidentally stole their code and put the company at (theoretical) risk of a lawsuit seems like a bad conversation starter with management.
Also it seems like in the original comment they already admitted to breaching the copyright, so sending him money doesn't increase the chance of a lawsuit succeeding.
I like the thought though