One of the officers' jobs was to decide who could leave the army. The full meaning of this statement can be made explicit. (See: [[rc://en/ta/man/translate/figs-explicit]])
The officer is describing a situation that could possibly happen to a soldier. If a man who did not dedicate his house died in battle, another man could dedicate the house. Alternate translation: "so that he will not die in battle, because if he dies, another man could dedicate it"