I did indeed call Social Security one last time; turns out I didn't answer the question wrong after all, so now all we have to do is wait for mail from Social Security or Medicare; we'll have to send them Cliff's birth certificate, which they'll return. And life can go on normally.
By the way, there is a Medicare line to call. The trouble is, you have to be enrolled first and have a Medicare number before you can get through to someone. So that's why we initially had to go to Social Security.
The last couple of calls I made weren't so bad, because I knew what to expect and which parts to tune out. All of the real people I spoke with were very nice, so I have no complaints there.
Maybe somebody learned something from my experience. If nothing else, you know what to expect when you call the Social Security phone number. Above all else, do not call on Monday or at the first of the month; but the robot tells you that at the beginning of her speech.