We could NOT operate that flight as there was a large part of the flight around Afghanistan where the minimum safe altitude was something like 14,000 feet (from memory), and had we lost the other engine or its pneumatics we could not have descended low enough (with NO press/aircon) and did not carry enough (pax) oxygen to stay at altitude.
Airsupport,
You can have a depressurisation even with two packs operating. Where I am it's a requirement to have a depressurisation strategy and a proven escape route any time flying over areas with MORAs above 10 000'. Being on one pack or two shouldn't make any difference, should it?