Surely it can't be that hard to move a wide and two teenagers from Sydney to Wellington?
Pretty sure it's hard to move teenagers anywhere; they have their groups of friends pretty firmly entrenched by that point. If they were older or younger it's different.
Good for you.
Also; if he lives in Melbourne and they stay in Sydney - a 90 min domestic flight is far easier than a 3-4 hour international one, especially considering he would have games against the Jets/Sydney/WSW/CCM where he'd be in NSW
Totally doable, unfortunately