(gimp-ellipse-select drawableOfImage 690 80 26 26 CHANNEL-OP-REPLACE 1 1 10) ;select an ellipse, feathered
This is not correct, "selections" are made on an image basis, the layer does not matter.
(gimp-edit-clear openedImage) ;clear selected area of image.... doesn't work
This is not correct. You want to clear the drawable, not the image*. As you do in the following:
;(gimp-edit-clear (car (gimp-image-get-active-drawable openedImage))) ;this doesn't work either
Assuming you have not commented out that line in your script (and you fix the selection), this should work.
* An "image" in GIMP parlance is merely a list of properties (width, height, name, type, etc) and links which point to the actual graphical elements of the image (layers, masks, and selections/channels -- i.e., "drawables"). You never "paint" or "draw" on the image per se, you always paint (or erase, or filter, or otherwise change the graphical content) on a "drawable" that belongs to the image.