What you are suggesting is that the time to discover faults with the air vehicle is when our troops on the ground are depending upon it? Without knowing what the contingency plans were, there is no reason to suppose that the drone operators did anything wrong at this stage.
A British operated Hermes 450 was lost at Camp Bastion, with the root cause being a blocked oil feed pipe due to the engine oil reacting with the plasticizer in the pipe.
Hermes 450 ZK515 loss Synthetic training won't bring things like this to light.