Looked into why the 2nd row headrests don't move or extend really and why they even have a button to fool us into thinking they do. Here is the reason
Remove headrests 2nd row
The headrest's upward movement is constrained by the cable that folds the headrest during Stow'n Go, as well as a star type lock washer (although the presence of this seems to depend on when yours was built - some reports have shown that earlier builds did not have this installed).
So this makes sense now and all of us who were trying to get those headrests to budge we can forget it now lol