Absolutely! Go for it
Personally, I set up speakers in my juke, just because it felt a little more "authentic".
But, you could always setup a button on the juke that triggers a script to toggle between the internal speakers and some external audio out port. Then hook up your airport to that and problem solved.
Or just always stream from the juke and choose that input on your yamaha system when you actually want to listen to it elsewhere.
Lots of ways to skin that cat