Which VO2Max figure is correct? (The perils of relying on the Internet)

I have just run 2.42km in 11 minutes and 17 seconds.

According to this site that means I have a VO2Max of 46.3 and I am in the top 10% of 47-year-olds. Seems unlikely, but I would not complain if it were true.

According to this site, though, I have a Vo2Max of 39.4 and this site rates that as (roughly) the 58th centile – better than average but not massively so.

Any expert care to comment?