[tux3]

>The way I read it

Looks right to me. She received a document from the Social Security Board with a made up SSN on it, and thought it was hers. It's not a joke, just an example of how people can get confused by real-looking fake numbers.

This can be said to be the fault of the board in the sense that after dealing with the 1938 incident they could have learned that this is confusing to some people, and for example printed 219-09-XXXX instead.