The deal is yet to be rubber stamped by the NRL.
"We'll be investigating the proposal with the NRL when they reopen on Monday,'' Roosters chief operating officer Brian Canavan told News Corp.
Fittler will be 42 when the two-day tournament starts in New Zealand on February 15.
He played the last of his 336 first-grade games in 2004, then coached the Roosters from 2007-2009.
He won the 1991 premiership with the Panthers and led the Roosters to victory over the Warriors in the 2002 grand final.
The Roosters have been drawn in one of the toughest groups on paper - alongside the Broncos, Bulldogs and Eels.
All 16 NRL teams will compete in the two-day competition, with many top NRL players on view - as opposed to many rugby sevens tournaments where players are lesser known.
Tournament rules stipulate at least 12 of each club's top 25 salary-capped players as well as one top-five player must take part.
There is A2.25 million prizemoney on offer, with the winning club receiving A$500,000.
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- AAP/Herald online