If it was originally used in a government publication, it belongs to the government, not the person who wrote it for the government. Though Michelle Antoinette wasn't officially a government employee and had no salary, the government certainly spent plenty on her staff and upkeep, so effectively, she was just that.
Thank you; you said what I was thinking but couldn’t articulate. What goes out under a First Lady’s name, I would assume, is written by bureaucrats.