I just figured this out and was going to delete my question, but maybe this will help other people…
(There still is a part I’d love some help with though!!)
The problem is that by default Photo Mechanic combines image types in the view. So the fact that I have both the raw file, and in a subdirectory, the jpeg of that file, for some reason, the keyword search fails. Worse, if I uncheck the Combined Images” in the View , this doesn’t fix the problem until I do ANOTHER search. Worse yet, if I uncheck the Combined Images”, it doesn’t remember the setting, so I have to remember that every time I want to search I need to:
1. Open the contact sheet
2. Uncheck the Combined Images” checkmark
3. Perform my keyword search
4. Change the dropdown to “Selected” (because even if you tell the “Find” dialog to look In: “All items”, it doesn’t… ACTUALLY look in all items unless you also have the “Selected” dropdown set to “All” instead of “Selected” because… reasons I don’t comprehend)
Do I have a solution, but it obviously feels very convoluted. Is there a better way?
On the upside, the performance of the search is EXCELLENT!

Thanks,
-Verxion