In today's IGN video, they showed the huayangosaurus in the game!

Huayangosaurus is basically one of 6 species of stegosaurs from the Dashanpu/Shaximiao Formations of China. It is basically the same formation were you find such species as the giant sauropods Mamenchisaurus, Omeisaurus & the metricanthosaurian Yangchuanosaurus.
Still I think we may have solved the mystery of the Asian stegosaur. I had heard some claiming it was likely going to be either Chialingosaurus, Chungkingosaurus or Toujiangosaurus - as these are the more well known species of Asian stegosaurs.