。
His pride wouldn't let him accept the reward.
Literal
Reward [object-を] receive [nominalizer-の] [object-を] his pride [subject-が] did-not-permit
The grammatical subject is プライド, not the person. The nominalized clause 報酬を受け取るの serves as the object of 許す. Two を particles appear — the inner one belongs to the nominalized clause, the outer to the main clause. This stacking is natural Japanese despite what some textbooks caution.