But despite trying multiple variations based on what I'm reading in the forums here, it's just not working. I'm sure the answer is simple, but I'm missing it.
First off, Hazel does recognize that the files I want deleted are duplicates (even warning me in the pop-up that it might delete them):

And as you can see I have the "Throw Away: Duplicate Files" checked:

And I'm telling it to look in subfolders:

But despite forcing runs and waiting a day and checking and unchecking that box, the duplicates still remain.
What am I doing wrong?