>I'm wondering what they could have done differently here.

It appears there were too many sources of confusion. GPS jamming, moonless night, busy ATC, not planning on VFR before takeoff, 20 minute short flight, instrument approach disabled, young pilots, mountains, and perhaps others.

Flight safety is about removing entropy and there were several steps which could have been taken, including not flying at all because of forced VFR on a moonless night near mountains.