New Zealand will face the Kangaroos at Brisbane's Suncorp Stadium for the 2026 title of the world's best rugby league nation.
Phoenix Crossland returned from suspension off the bench for the Kiwis against Tonga, playing before his home crowd at McDonald Jones Stadium.
"(It was) probably one of the darkest times in my life and it was just a weird month," he told Newswire after the victory.
Crossland received a four-game ban for a hip-drop tackle on Nathan Cleary, who suffered a compound fracture and required emergency surgery.
The suspension ruled Crossland out of Newcastle's Grand Final appearance and New Zealand's pool matches.
"It didn't really feel real the whole time; probably hasn't until tonight, getting back out there. It was just really nice to get back out and do what I love doing."
After Newcastle came close to the NRL premiership, Crossland said winning the World Cup final could help end a difficult month on a high.
"But I get to right a few wrongs next week, fingers crossed, and to win the World Cup is probably the only thing that could sort of make the past month somewhat worth it."