Oh! That's true. They're probably very confused with how lost they are. Let's go in!

[She recalls Altareon to the ball and heads toward the lab, knocking before just opening the door.]

That's likely the case. I don't know where they went from their last known appearance, but whatever is bringing people in must have its own criteria -- or it's sufficiently different from how some people will try to willingly summon them. It would seem to be a property of the region itself.