4, 5, 20

ἡνίκα οἱ φίλοι αὐτοῦ τοὺς ἐκείνου ἐχθροὺς ἀπολλύουσιν.
Both αὐτοῦ and ἐκείνου refer to the same person. First, could he use the reflexive here instead of both? second, does he use two pronouns just for the sake of diversification?