Well, I've never actually tried to make sense outta the message. But, yea, I guess it would be because of Adel all they way up there.

G-Garden seemed to have disappeared off the face of the FFVIII world. (SPOILER)Edea returns to her orphanage after she starts being 'Edea' again and Seifer goes to find the Lunatic Pandora under Ultimecia's (who possessed Rinoa) order. So, I dunno where it went. It's not in Galbadia or anywhere else in the world :S

I actually thought that the Griever GF existed in the ring already. It seemed that all the other orphanage gang people remembered slightly more, like they remembered Seifer and Edea. All Squall could remember was Sis, who he couldn't even put a name to. It would make sense, if Squall had a GF for longer than everyone else ie. Griever.