
I'm just echoing eveyone else. if they are willing to pay the expense it can't be a bad family. You can still keep in contact, there's e-mail and there's Skype (Free skype to skype calls, might be worth suggesting s you can keep in contact! If they have a web cam you can see the dog too!) My partners parents use it to keep in contcat with their friends all over the world for free and so their freidns can see how the dogs are now coping in UK. It's fantatsic and easy to use once you know how.
I would be givingthese owners as much support as possible, not asking to take back there much loved family pet. I would be offering to do all I can to help them move the dog over safely, does she need to be taken to airport seperatly, what if she doesn't get on the same flight as them? Will she stay at airport for night or will you make arrangements and be on call should any help be needed this end?
I think it's better they are taking her with them, they could have dumped her in rescue and not told you a thing.