Quinlan, who played 12 games and scored six tries for Saints in 2015, is off-contract at St George Illawarra at the end of this year.
The 23-year old started this season in the NSW Cup but has been featuring regularly for the Dragons in recent weeks.
Quinlan has made four appearances for the joint-venture at fullback in 2016, scoring one try and setting one up.
He missed this weekend’s match against because of injury.
Quinlan can play at scrum-half and stand-off, as well as at fullback.