FullWings,
are you sure the flight path vector does not require air data?
While the IRU's do have vertical acceleration as an output (that's where the Instantaneous in IVSI comes from and the reason the VSI needle will jump around 0 when climbing / descending with statics blocked), I do not think that vertical velocity is also an output. So where would the vertical trajectory info come from? NSEU - any clues?