Wa-atānā ... khaṭb introduces news of a serious affair; zaʿamū identifies a claim made by opponents; and yakhliṭūna al-barīʾ bi-dhī al-dhanb reveals its faulty reasoning.
The poet does not simply claim that nothing occurred. His key objection is that alleging affiliation cannot itself establish guilt for every member of a community. This distinction clarifies the argument rather than treating the passage as undifferentiated boasting.