McCullum is the selected captain so must play.
Both have fitness issues so it could be taken out of our hands. But McCullum goes too hard at the ball to be a good opener and looks tortured every time he has to wait out an opening bowler or eke out a few singles. Coming in to join in the flaying of a bowling attack suits him.
They might look at Boult Southee Wagner Sodhi Williamson Ryder as enough bowling....Where do you then bat Ryder though? in my opinion the side has a settled and balanced feel to it, with Ryder possibly only coming in for McCullum or Williamson.
Edit: having watched some highlights Anderson picked up two key wickets on a green swinging seamer- the man in form Bravo and the best in this match in Edwards. Key wickets and important in the win.