Fresh after signing a lifetime deal with the Sharks until the end of 2029, Hynes stepped up when it mattered to send Blayke Brailey over the line to break a 12-12 deadlock with 10 minutes remaining.
He then helped the Sharks gain further momentum for Braden Hamlin-Uele to bust up the middle before Brailey sent Briton Nikora over the line in the following play.
It was an important win for Hynes and the home side, who were coming off the bye and the shock loss to the Warriors in Round 5.