Never was anything to stop a departing passenger theoretically returning to the main lounge once on the 80 gates on Sat 2...we advised that if asked but with the added proviso "it is a bit of a walk" ie over the walk bridge & back.
Same with Sat 3 once in the main lounge freedom to move between the two...except for the distances to walk of course.
Although in the same satellite domestic & international are on different levels & totally segregated obviously.
Due to the satellite transit train layout there is no way back from Sat 2 international departures to the main lounge & we emphasized that to departing pax if asked.Also for international pax there is no route/transfer between Sat`s 1 & 2 once in either.
To exit Sat 2 international departures with airside passes we would go down one level to Sat 2 arrivals & access thu a security side door the domestic lounge & walk the bridge to the main lounge.