I believe Ward's appearance is dependant on the Timber Maniacs you collect. If you enter Selphie's page concerning Laguna, you'll find explanations of all the Timber Maniacs articles you've collected. One shows a picture of the area in which you fight the Ruby Dragon. In her notes Selphie says that she can't see Ward. This is the key, I think. If you view this article prior to the sequence, then you will not have Ward - if you don't view it at all then Ward will appear, though when you look at the article post event, only Laguna and Kiros will be in the picture.

I think this is the reason, though if anyone else has spotted something different, please correct me.