Oxygen masks deploy automatically when airplane is above 10,000 feet more or less
only when
Cabin altitude rises above 10 000 feet (more accurate: above 13 500 to 14 000 ft, depending on type).
It's very unlikely that they had an engine fire/overheat/smoke and a cabin decompression at the same time. This has never happened so far I know. It's physically not very likely, because if air is being blown overboard, smoke is less likely to happen.