>>35395299The only banned episodes that were never ever aired in the US are the Porygon, Safari Zone and Ice Cave episodes, as well as the three recaps from Hoenn and Sinnoh. That would indeed make the episode where Kukui marries Burnet the 1000th episode.
But as you said, out of the DP/BW/XY/Mega special episodes, only the mega ones and the first XY special were dubbed, so their count is off either way, and the 1000th episode should be SM060.