I agree if VO2 is going to be stated as "one of the highest measured" there should be more information. Taking the given 2k time of 5:36, plus his bio says he's 97 kg, and plugging it into the C2 VO2 max calculator it comes up with 75.10. A world class number but not near the 90's the XC skiiers hit. That page states that it's accurate to 1.5%, but this is for someone at the limits. 
 C2 VO2 => http://www.concept2.com/us/interactive/calculators/vo2max.asp