"We have been completely transparent with both the Sharks and the Cowboys, who have been terrific about it and very supportive."
The NFL Management Council informed clubs of the trial to be held on November 26.
"Jason Taumalolo and Valentine Holmes, two of the best players in Australia's National Rugby League, have scheduled a work-out for NFL clubs this Saturday," a statement obtained by the Roar said.
"These players are considered NFL free agents and are eligible to sign with clubs after the club has received written permission from the player's National Rugby League club."
The Cowboys said Taumalalo would test with the full backing of the club.
"The North Queensland Cowboys are aware that player Jason Taumalolo is returning from the Four Nations tournament via the USA where he will undergo testing in front of NFL scouts," the club said.
Taumalolo's interest comes less than two months after he put rumours of a cross- code move to bed by declaring he wanted to become an NRL great following his Dally M medal win.
"My plan is to retire playing rugby league and that hasn't changed over the last little while," he said after winning the gong alongside Cooper Cronk.
Both Taumalolo and Cronulla's Holmes are believed to be deep into negotiations to remain with their NRL clubs beyond the end of the 2017 season.
However the latest development could throw a spanner in the works, and comes less than a year after South Sydney forward Thomas Burgess tested with New York Giants.
The Rabbitohs prop also went with his club's blessing, and returned to play in the 2016 season.
The 2016-17 NFL season is into its 11th week with Super Bowl LI on February 5.
- AAP