One little extra point, if the supply tanks were faulty showing full (my personal theory), the CAD Amber fuel caution does not operate when supply tanks go below 32ish. See NWEM pictures for proof. The board 'found no evidence of CAD fuel illuminating'.
Sadly my good friend ignored a critical warning and continued on task. He must have been misled by the gauges. To say there was no evidence to show a fuel system fault is a poor conclusion. That moves blame from 50:50 pilot:manufacturer to 100% pilot. Sad, but not unexpected