It's a good idea to do the following:
Track your NDB with the BRG1 of the RMI needle in the G1000, and simultaneously select the GPS1 NAV source in which you will put in the NDB station as a GPS waypoint. That way, in straight and level flight, both needles will overlap and point equally towards the station, and in turns you will suffer from DIP in the BRG1 pointer, but you will always have a real and constant indication of the station with the GPS pointer.
If the CFI asks, then just say you are tracking with the BRG1 and you are using the GPS to improve situational awareness during turns.