I, like the original poster, am curious about my Vo2 Max.
I know very little about the test that you describe. However, a few years back on my 45th birthday I decided to take a “stress test,” this included a treadmill which inclined and went faster every 1:30.
I rode the treadmill for over 20:00 and my heart rate rose to 175 BPM by the end of test. I could have gone on longer, but the doctor stopped the test because he stated that he had all the information that he needed.
The elevation was up around 18-19 if I remember correctly. The speed only at 5.5 mph.
It was an interesting experience. I never found out what my Vo2 Max was since it was a typical stress test to see my chances of a heart attack (which by the way was zero).
The workout was like doing high rep squats with little or no weight. It was difficult, but I think I could have gone another minute or two if I had to.
I mention this as I would like to know if I can figure my own Vo2 Max from the above test.