A crossfeed valve failure in the fuel system might, but each engine has seperate fuel lines for redundancy. There would have to be more than one failure at a time ie: an electrical bus failure canceling out the redundancy. but if those were the case the pilot would have known immedieately and re-routed power. A possible fuel heater system failure allowing ice build-up in the fuel lines. Or incompatable mixed fuels clogging the fuel filters, perhaps? Even an excessive AOA caused by agressive maneuvering could flame out both engines. I'd have to see the data from the recorder to do any more than speculate. Hell, even a disconnected cannon (electrical) plug that someone missed during inspetion could be the culprit. I used to see those things come back from training flights with all kinds of screws & rivets missing.
Short answer; a lot could cause it. Most of which is unlikely except pilot error. After that fuel feed failures.