Can’t they fly on one engine?
Well, we are talking takeoff, not cruise here. So very probably not. Maybe on two, but if they were on the same side, it would take an outstanding pilot and a lot of luck.
I recall the plane in question didn’t have much in the way of cargo, so again, the loss of a single engine shouldn’t have been determinative of the outcome.
Absent facts, I’d speculate a combination of mechanical fault and pilot error.