Implied rationale is not an explicit causal statement

Defining the Subject by a Relative Pronoun: Purposes and Rhetorical Applications

Implied rationale works by making a meaningful relationship between the relative clause and the predicate apparent. It does not necessarily state an exhaustive or formally established cause. Treating every such hint as explicit causation would overread the rhetorical form.

Contrast:
«الذي صدق نجا» — The one who told the truth escaped: the clause may suggest why escape occurred.
«نجا لأنه صدق» — He escaped because he told the truth: the causal relation is directly expressed with «لأنه».

Imāʾ (الإيماء) is about an indicated relation. Grammar and style alone do not prove every causal detail of an actual event.