SpiraMirabilis
Possible Subversive
"Localizer backtrack" is not standard phraseology*, so I'm not surprised you confused it with a backcourse. Going into an unfamiliar sim they're not going to expect you to fly to PTS standards, just show that you're trainable.
* Although "backtrack" is ICAO phraseology to indicate taxiing in the opposite direction of the runway.
* Although "backtrack" is ICAO phraseology to indicate taxiing in the opposite direction of the runway.