Welp. I ordered a new STP to try,
STP-Fitz. So far, the experience has been stellar. I received a notification that it was to be sent out today (I had let him know I'm moving at the end of August and wanted to be sure I'd receive it before then).
The design is interesting and may be better for me. If this doesn't work, I may resort to the "coffee lid" option. I just cannot get the medicine spoon option to work for me.