Nothing wrong in taking the last bit of flap right at the bottom. I believe the B777 can land with Flap 25 or Flap 30 anyway, so it won't get any sort of config warning on the way down like other ac will. I guess Flap 30 just makes it easier to stop at the bottom, ie for shorter runways.
I don't think the in-flight data is a very accurate way to extract actual landing speeds etc.