So...let me help. They typically don't "certify" the test samples, at least in my experience. They will "certify" the equipment to the specific samples. To do this they send their tech out and the tech checks the equipment against the test samples. I've seen companies embed serial numbers on the test pieces and attached that information to the equipment certification. If I were you ask them about the equipment certification with specific test samples.
The reason IT SHOULD be done this way is equipment can be influenced by moisture, heat, humidity, electrical interference, vibration, etc. To truly certify the equipment it SHOULD be done in your facility with it setup in your line.