According to Higgins here
NY1 | 24 Hour Local News | Top Stories | Jet Slowly Lifted From Icy Hudson River
"The crew selected Flaps 2....."
As I understand it, in order to have flap operation, the Y or G system would have to be pressurized. As others have said, this can still occur in a double out situation where the engines continue to windmill.
What a great triple-redundant RAT system
