Drug Free Sport NZ backed the decision by the UK Anti-Doping agency to prevent the Kiwis using a synthetic steroid on injured utility Thomas Leuluai.
It is entirely academic now, with Leuluai ruled out for the rest of the tournament, but the New Zealand camp had hoped to circumnavigate the UKAD decision to prohibit the use of prednisone by getting approval from Drug Free Sport NZ.
There were no guarantees they would have been able to use it on Leuluai even if Drug Free Sport NZ had given their approval because UKAD are contracted by Rugby League World Cup 2013 for the duration of the tournament. Drug Free Sport NZ ruled over the weekend that they were "obliged" to follow UKAD's decision, according to a Kiwis spokesman.
Leuluai's World Cup lasted less than five minutes when it was apparent his groin injury wasn't up to playing when he attempted to take the field against Papua New Guinea on Saturday morning (NZT).
The 28-year-old will remain with the Kiwis for the rest of the tournament and, as a member of the senior leadership group and with eight years' experience playing in the UK, has played an important role off the field. The Warriors are happy for him to stay in the UK, especially as most of the club's medical team are with the Kiwis.
Leuluai is the only player unavailable to take on Scotland in their quarter-final at Headingley on Saturday morning (NZT) but the Kiwis weren't taking any risks with a handful of other players who sat out training overnight.
Sonny Bill Williams (shoulder and flu), Manu Vatuvei (knee), Josh Hoffman (shoulder) and Frank Pritchard (knee) skipped training but were all precautionary.
"Where we are at this stage of the tournament, there's no point taking risks with these guys at the start of the week," Kiwis manager Tony Iro said. "Apart from Thomas, I expect everyone to be available [to play Scotland]."
Few expected Scotland to get this far in the tournament, with most predicting Tonga to emerge from Group C. Scotland are undefeated - they beat Tonga (26-24) and the US (22-8) and drew with Italy (30-30) - but realistic about their chances against the defending world champions.
"It will be a tough game obviously, but it's amazing that we've made the last eight of the World Cup," Scotland halfback Peter Wallace said. "The Kiwis aren't super-human. They're a good team but it'll take a massive effort to beat them.
"We'll do our best and give it our all and see where that takes us. We've got nothing to lose and it will possibly be the last World Cup game of a few of the boys so it will be a special occasion for us."
Wallace is one of three NRL-based players in the Scotland squad, along with Titans prop Luke Douglas and Cowboys centre Kane Linnett.
He will return to Penrith next season after six years with the Broncos, where he will come under the watch of coach Ivan Cleary who has been impressed by the Bravehearts at this tournament.
"They haven't lost yet so are very committed and look like the play for each other," the Kiwis assistant coach said. "It's going to be a tough game. For us, it's about getting better ourselves. If we can improve on what we are doing, hopefully that's enough."
Cleary was later due to visit Cameron Ciraldo in hospital after the Italy and Panthers second-rower suffered a lacerated pancreas in a thunderous tackle by Tonga and Warriors centre Konrad Hurrell yesterday. Ciraldo will remain in the UK and is expected to have surgery.
The Kiwis will name their side to play Scotland on Thursday morning (NZT), with most interest around the makeup of their four-prop rotation.