Well, it turns out my problem was something else entirely... I finally found the thumbnail in the library for the item. It was called "Jeans Dark" and has a "conforming" label on it. The missing .obj is "Jeans Dark_164445978.obj". It was in a folder called WW Ryan 2.

IIRC, that would be an item I fitted to Ryan 2 with the Wardrobe Wizard? Wow, I haven't used that since right before my drive failed. Now I have to figure out which jeans I used and how I fitted them before.

Thanks for the assistance!