Even if Greens pick up one more seat and Labour could form a 62-60 seat Government with the Greens, with Maori Party support, look at what the two options may be:
1) Labour/Progressive/Greens with 58 seats and four seats on confidence and supply from Maori Party.
2) Labour/Progressive with 51 seats and 17 seats on confidence and supply from Greens, NZ First and United Future (plus likely support on most issues from Maori Party)
The more I think about it, the worst it looks for the Greens. They face being merely one of four parties outside Government, yet supporting the Government.