I passed the page test!
I think it was a bit easier than I was led to believe. On the phone, I was told the test had to be completed in six minutes. But before the actual test, I was told I had "up to 10 minutes," with points deducted for time over six minutes.
When I finished, I said, "If I'm under six minutes, I'd like to double-check my work." The reply: "You're not under." Oh shit! But two people checked the books, and informed me that I passed. Whew!
It will be a while until I'm actually hired and start work, but what felt like a huge hurdle is behind me.