This exercise is an attempt to enlist the assistance of the GeoGebra community with identifying the source of the computer-generated discrepancy. I am confident enough with GeoGebra that I doubt that it is a bug with the tool.
That said, I have a massive headache from spending every available moment of the last few days trying to discern the apparent bug. LOL
Perhaps, I (as well as others in the community) will learn something technical which sheds light on the puzzle.