It's not a sequel; it's a stand alone using one character. It reads like two novels jammed together. One is about a massive 'fake news' story that lives on decades after it's debunked, and the other is about a computer simulation/afterlife. Not his best, imho.
A catastrophic event renders the earth a ticking time bomb. In a feverish race against the inevitable, nations around the globe band together to devise an ambitious plan to ensure the survival of humanity far beyond our atmosphere, in outer space.
I didn't give a description of the plot because I couldn't come up with something that really conveyed what the book was like. The one you gave is decent, but it doesn't convey just how much of it is about the people. It's hard scifi, no nonsense, but the heart and soul of it is its characters.