Edit: The comment you deleted right before I could reply was good! I think people would enjoy and benefit from your description of how the process works if you're willing to repost it.
As you noted the reliability requirement did in fact flow down from an engineering requirement which is why they exceeded the minimum FMEA standards. There's no official guidance on where and how exactly to track that information so they put it in the usual place but in an unusual way. The lack of a standard during Voyager's time probably impacted the visibility of the work more than the substance.