Thank you both for the assistance and suggestions. I will try working the button with some rubbing alcohol. I'm experienced with electrical work, have a soldering iron, but not much experience with component level changes on a board of small dense connections. In any case I probably will open it up to take a look if this doesn't work. I'll update this thread.
As I said, everything else, keys, buttons, work marvelously, and the condition appears to be consistent with the previous owner's assertion that it was rarely used. The tiny function button would probably be the most used button, as it's required for so much. I don't think there's any way around using it. Thanks for the manual.
