Yes, but SA have their rules and I would suggest that the majority of those who have two passports haven't notified SA of their new citizenship.
if you are in the public eye (like Wynne and for that matter Fitzgerald), then it is playing with fire.
Fitzgerald however has done the right thing. He is a Japanese citizen and is not messing with their rules. He isn't playing for New Zealand and is playing as a Japense citizen in the J league.
Wynne however played in a full international for NZ even before he had a NZ passport!! Technically not messing with SA citizenship rules at that point. NZ football have never explained that little fire cracker of an issue and this also should also be a major part of the inquiry (when it happens - after we lose this appeal).
Someone needs to accept responsibility for that. There is no hiding behind pleading dumb and stupid interpretations of statutes on that issue.