مَا فَحَصَ الْمُرَاقِبُ إِلَّا الْمَوَازِينَ.
The inspector examined only scales, not other things.
مَا فَحَصَ الْمَوَازِينَ إِلَّا الْمُرَاقِبُ.
No one but the inspector examined the scales.
The first restricts the object; the second restricts the agent. If the dispute concerns which objects were inspected, the first is responsive. If it concerns who carried out the examination, the second addresses the contested point.
It is not enough to say that both contain restriction. Identify the restricted element, its syntactic position, the excluded alternatives, and the conversational context.