Moe says Ken's injury was caused by a mortar fragment. But in the opening scenes there are no indications of mortars or any artillery.
The opening beach scenes show the beach as very rocky. The following scenes after the battle show a continuous sandy beach with an offshore reef,
When Moe takes Ken to the cave, a bird call is heard. The call is of a Kookaburra, a bird only found on the Australian mainland, not on any tropical islands.
None of the Marines carry a trenching tool on their back packs.
No matter what the time of day, there is always enough light in the cave to see the men.
In the opening battle scene, some soldiers fire multiple shots as though they were using semi-automatic weapons when they are obviously carrying bolt-action rifles.
The Japanese would not leave the bodies unburied on the beach nor loot items from only one dead body. They would search every dead soldier for useful information, equipment, and food.
Moe throws Ken's helmet away when he discovers him on the beach. He would keep any equipment that would help protect them and keep them alive.;
Ken is seen to use his legs when he fights the Japanese soldier.