إِنَّهَا عَلَيْهِمْ مُؤْصَدَةٌ
Indeed, it will be closed over them. (الهمزة: 8)
Innahā provides emphasis, and the pronoun points back to the fire. Placing ʿalayhim before mūṣadah highlights those upon whom it is closed. The participle conveys enclosure, reinforcing the picture of finality.
Fronting a prepositional phrase does not invariably prove exclusivity. In this setting, focus, prominence, and emphasis are well supported; a categorical restriction excluding every other relation would require further evidence.