The clamp makes one bracket flat and tips the next

We're looking at a nest for FR10-loaded bracket inspection, and two bench samples settle against different contacts even though both fit the drawing. Closing the clamp flattens one and tips the other. Before I accept the proposed bigger clamp, I'd like to know which contacts are meant to locate and which are just there to stop flex. Who normally owns that explanation when tooling and inspection came from different suppliers?