Can I connect the ground wire for my dryer to a different hole in the chassis?
Taking a closer look, there is another ground symbol hiding behind the terminal of the red wire, just above and to the left of the strain relief bracket (see first photo in the question---the first horizontal line of the ground symbol is just visible above the terminal for the red wire). This is more consistent with the diagram in the installation instructions than I had thought.  Between that and the text of step 7 of the installation instructions (which states that the hole for the ground screw is above the strain relief bracket rather than on the strain relief bracket), I feel fairly confident that I've connected ground to the correct spot. Thank you everyone!