Napa has just begun his three-year contract at the Bulldogs, with the club releasing it's second statement surrounding the issue in as many days.
"The club is aware of a further social media video that has emerged today that was taken several years ago," the statement read.
"The club can confirm that Dylan Napa has received legal representation and advice from senior legal council, as well as made contact with the NSW Police.
"The club is supportive of Dylan and is providing welfare support.
"The club will not be making further comment at this time."
Napa won the premiership with the Roosters last year but made the move to the Bulldogs for the 2019 season.
He joined the club on a three-year deal, replacing former Bulldogs prop David Klemmer, who has moved to Newcastle.
Napa debuted for the Roosters in 2013 and before heading to Belmore, had spent his entire NRL career at the Bondi club. He played 122 matches for the Tri-Colours, during which time he made a name for himself as one of the biggest hitting forwards in the competition.
He's played five Origins for the Maroons.