I am not a DCC user so I do not know if DCC boards have coupler outputs. Most DCC operators use Kadee couplers. I do know the DCC system is coupler capable because all the Lionel S gauge Legacy engines also operate on DCC and the couplers can be actuated.
Lionel's system is still proprietary Legacy. There is no separate DCC controller, but additional code that accepts the DCC signal and decodes it for the Legacy electronics.
Any DCC decoder output to control couplers would have to be a pulse output with sufficient current capacity, not an on/off type output toggled by the controller.