I had him do that for the "next track" button (i.e., the "seek +" button) up above, and it came out as "5b"
Yeah, I saw that. Part of the problem here is that we have a guy who has never used a working stalk before, so things will be very confusing for him. And he may not notice when things actually work or not.
So, perhaps he could also report here exactly what each button generates on the display, going through all of the buttons 2-3 times to get an average.