Is certainly possible to have a running vertical that is significantly higher than standing vert. The HJ works off multiple planes and someone with a good approach and good speed uses the curve, their speed, the vertical power, and their hip rotation over the bar to propel them. John Strang and Eric are both good examples. John cannot even jump as high as I can from standing, but can HJ a good 12″ higher than I can.
I would argue though, that there is almost no way Holm has a true VJ of only 23″. 33″ I’d believe.