The test renders were simplified. The object is being used in a full scene in an enclosed warehouse with over 100 figures and objects, and it acts exactly the same in the scene.

I sort of fixed it, but I'm still not sure why it happened or why what I did should be necessary. I looked at the materials from the original object, and it was using an Sphere Map. So I inserted one between the JPG file and the Reflection Node. It makes the metal a lot brighter than the original material is supposed to be, but i can adjust that with the Color on the Sphere Map.