Star shooter Maria Tutaia also returns after being sidelined for nearly six months with a foot injury sustained in Glasgow last year.
Taumaunu said that while it would be good to get another look at the likes of Halpenny, Francois and Lees in the Ferns environment, that wasn't the selectors' motivation when picking the group for Fiji.
"They were selected because they turned up in good shape and have clearly done some work," said Taumaunu.
"I am delighted that we can build the depth of the group, but the main criterion for selection of this group was progress made in conditioning.
"Those who aren't in the group will stay behind [in camp in Auckland] and will continue to work with the trainer."
The big positive in yesterday's announcement was the return of Tutaia, who will bring much-needed firepower to the struggling shooting end.
While their Pacific Island rivals will not offer much in the way of resistance for the Ferns, the New Zealand side will be relieved to have the shooting ace back on court in plenty of time to build her form and confidence before the World Cup in August.
Tutaia was taking only a limited part in Mystics training sessions before Christmas, but made strong progress at this week's squad camp in Auckland, where the team were put through a battery of fitness tests, conditioning sessions and skills work.
"We're not prepared to take anyone who has to be managed next week, it's too hard and we're too close to the start of ANZ to do that," said Taumaunu.
"I have listened very carefully to medical advice and I'm told Maria is absolutely ready to go."
Tutaia is also confident about her fitness.
"I managed to do every thing that all the girls have done so I haven't been the precious one in camp. Everything's gone well and I haven't had any niggles with my foot so hopefully it stays like that.
"I was always targeting this tour for me to come back. I've been working really hard these last five-and-a-half months - things get really tedious when you're working by yourself in the gym, so I'm so pleased to be back."
The Ferns leave for Suva tomorrow and will take on Fiji in the series opener in Monday.
Oceania Netball Series
•
January 19:
Silver Ferns v Fiji, 7.30pm.
• January 20: Silver Ferns v Samoa, 7.30pm.
• January 21: Fiji v Samoa, 7.30pm.
• January 22: Silver Ferns v Fiji, 7.30pm.
• All games live on Sky Sport 1.
• Silver Ferns team: Laura Langman (tour captain), Katrina Grant (vice-captain), Jodi Brown, Maria Tutaia, Ellen Halpenny, Bailey Mes, Shannon Francois, Camilla Lees, Grace Rasmussen, Leana de Bruin, Phoenix Karaka, Kayla Cullen.