Can the commercial night cross country be done under IFR? The below doesn't mention anything about needing to be night IFR, so if you were to shoot an approach on this flight, would it be legal?  Also, if the instructor isn't a CFII, but PIC does have an instrument rating?

https://www.law.cornell.edu/cfr/text/14/61.129


  (iv) One 2-hour cross country flight in a single engine airplane in
  nighttime conditions that consists of a total straight-line distance
  of more than 100 nautical miles from the original point of departure;
  and
The regulation doesn't specify VFR or IFR, so you may complete that requirement in either.