Ok so pinouts.ru has it wrong on the #AAUI connector ordering for the last 7… And Wikipedia copied that.
The pin numbering on the connector image is correct, but they listed the pins in the reverse order of this numbering for the bottom row.
It seems much more logical to have the 5V pins together and the PWR ones as well.
And this Apple LC-PDS card shows it: supposedly reserved pins are used but not the supposedly data out ones.
Now I can see how they got confused, Apple seemed to have used a different pin numbering on the connector internally:
Instance de l'association G3L basée à Valence, Drôme, France