His dad got the all clear - a massive relief for everyone - and Moa had to be content with watching the tournament on television.
"It was difficult not playing," admitted Moa. "It was gratifying to watch the boys doing well but [also] disappointing not being part of it."
Aside from repaying Stephen Kearney's loyalty, Moa also needs to make an impression on Friday to stay one step ahead of the other contenders, with prop one of the most competitive positions in the New Zealand environment.
"[There are] such a number of quality front rowers who just happen to be Kiwis," said Moa. "Making the team is going to be harder and harder in the coming years. There is always someone someone knocking on the door [and] we have to do them proud. If you don't perform it's seen that they could have done the job."
But Moa is used to fighting the odds. After being a promising junior - he was selected for the national age group sides as a teenager, including the Junior Kiwis - he lost his way. With his NRL career stalling at Cronulla, he moved to Super League. Moa started well in England, before slipping into bad habits.
"I wasn't really professional enough in my preparation and training to become a footy player," said Moa. "In the middle stages of my career in England I was just cruising along.
I didn't really make that next step until I came across some experienced old heads who Craig Fitzgibbon and Mark 'O Meeley and I saw how they did things. I trained harder, prepared better and gradually things started working out for me."
Since then he has won a premiership with the Roosters and played four tests with the Kiwis. He offers a point of difference to most other New Zealand front rowers; he's built low to the ground and specialises in gaining quick play the balls. His impact will be crucial on Friday night, especially in the expected wet conditions.