I have a '92 Model M silver label which keys, one fateful day, stopped responding. Just 9 keys won't work. I've highlighted them in the image below. They don't seem to share a grid or sector but I could be wrong. I'm sure there are plenty of you GHers whom are way more knowledgeable than I in these matters. And that is why I ask this question of you, today.
Here's a list of the keys in question:
ESC
Caps Lock
Left Alt
G
H
'"
Up Arrow
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