Sione sustained a season-ending knee injury in Sydney and is recovering from a reconstructive surgery in Auckland.
The 27-year-old is expected to return to the side next season.
The Island nation team is expected to feature Neueli Leitufia and Motu Opetai in the competition after they were both handed three match bans in Sydney.
The duo missed out on Samoa’s 5th place final in Sydney against Ireland and the last two weeks of club rugby in Samoa, making up the three weeks.
Samoa is pooled with Sydney 7s champions, New Zealand, USA and Chile at the LA 7s.