I'm not sure he's even bagging out the Phoenix. Hanging around in Wellington, playing Handy Prem may earn you a gig here but seeing the world and trying to make it at a similar level (Portuguese Under-23s) is probably more appealing to an 18 year old.
They may both pan out, neither may pan out but one is where you have lived your whole life and the other is a chance to see the world and be noticed in front of a larger audience.
I think the most important thing is that he makes an Olympic squad at some stage in the next 4 years and doesn't go all 50 shades on us.