An interesting problem and hoping to see a good solution.
For the record (others reading this thread), when the Navigator is Open showing by Headers, you can search any word or phrase and the chapters containing that Word or Phrase will be Highlighted.
It would be ideal if Word allowed the Chapter Reference(Chapter/Heading# by Selected Heading Level) to be listed when creating the Index. OR if Word allowed Section Breaks as a property of a Style (like Page Breaks Before is allowed.)

I moved your question to a separate thread to get it better attention.

You can add chapter numbers to your page numbers and have them show up in an Index. I want to include the chapter number with the page number in the Header - how can I do this? by John McGhie, MVP

Note, this is not the place to get any changes made in Word nor the attention of developers at Microsoft. This is an independent user-to-user support forum. MS does not see anything you post here. The way to get their attention is through the feedback mechanisms.
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