Turns out he most likely did not:
BUENOS AIRES, March 21, 2013 (LifeSiteNews.com) - Miguel Woites, a confidant of Pope Francis while he was archbishop of Buenos Aires, is denying a widely publicized claim that the then-Cardinal Jorge Bergoglio suggested the endorsement of gay civil unions as an alternative to "homosexual marriage" during a private meeting with fellow bishops in 2010.
In an interview granted to the Catholic news agency ACI Prensa, Woites said that the story "isn't true. It's a complete error."
The principle source of the claim, Bergoglio biographer Sergio Rubín, "never said who told him, when they told him," said Woites. "It's not correct to write something like that out of thin air. That (New York Times) article was very criticized by the bishops. He certainly would have referred to unions of convenience but not that anything be legalized."
Related link: Bergoglio didn’t suggest endorsing homosexual civil unions in 2010, says confidant of new pope ~ LifeSiteNews