The only thing I see in that article about the appearance is a note recapping the general response by the public in the context of the movie. It’s the author of the FastCo piece that uses the phrase “important deliverable”. Sandberg may very well have pushed for the specific timing but it’s hard to draw that conclusion from the FastCo piece.

The Prize indicates that Facebook communications and Zuckerberg didn’t want to announce so close to the movie:

There was a complication, however. Another movie was scheduled to debut the same weekend: The Social Network, Aaron Sorkin’s fictionalized account of the founding of Facebook in which, it was already well known, Zuckerberg came off as an arrogant boy genius who betrayed a trusting friend on his way to fame and fortune. There was plenty of anxiety at Facebook headquarters about the potential of the movie, sure to be a box office blowout, to tarnish the company’s brand. Facebook’s communications team flatly advised Zuckerberg not to make such an attention-grabbing gesture of generosity just when The Social Network hit theaters. It would probably be criticized as a $ 100 million damage-control stunt, not seen as a bold and selfless commitment to a better tomorrow for children, senior advisers told him. Zuckerberg asked Booker, Christie, and Winfrey for a postponement, but they were determined to go ahead, largely because Booker wanted to use the marketing campaign for Waiting for Superman as a catalyst for raising the second $ 100 million. Zuckerberg said he then proposed making the gift anonymously. But again Booker, Christie, and Winfrey pushed back, saying they needed his name and cachet to attract donors. Zuckerberg said he did a rough calculation in his head and concluded that the number of people likely to see The Social Network was about two percent of the number who then logged on to Facebook every day. Let’s go ahead, he said.