Maroon, 29, is a pending unrestricted free agent with a modest $1.5-million salary cap hit.
He had been practising with the Oilers in recent days despite being made a healthy scratch in each of the team’s past three games, including Sunday’s 6-5 win over the Anaheim Ducks.
Maroon began his NHL career with the Ducks and was acquired by the Oilers in February 2016 for a fourth-round draft pick and prospect Martin Gernat.
Dudek, a 2014 sixth-round pick of the Devils, is finishing up his third season at Boston College.
Coming off yet another disappointing season in which the Oilers find themselves near the bottom of the NHL standings, general manager Peter Chiarelli has begun selling off assets.
The team sent defenceman Brandon Davidson to the New York Islanders Saturday and received a 2019 third-round pick. Then, Chiarelli moved forward Mark Letestu and acquired Pontus Aberg in a three-team trade with the Columbus Blue Jackets and Nashville Predators.
The Devils, meanwhile, are bulking up for a playoff run having acquired Michael Grabner from the New York Rangers last week.