I think the age thing is a myth. My first two gliders were a year and a half old when I got them and they bonded JUST fine. In fact, I later got a 6 month OOP female who was scared to death and has taken months to actually get to where she will approach me.
I think that the reason people think that about 'older' gliders is because usually these 'older' gliders are coming from homes who have lost interest and no longer handle the gliders. So sometimes these gliders have a little more time trusting again. But not always!
Basically, You guys should be fine.
Welcome to the site and to having gliders! There are a lot of very informative posts here!