I doubt the Trollocs were after Tylee, because otherwise they would have used overwhelming force (in order to prevent what happened: Tylee convincing Tuon of the Darkspawn threat, and being promoted).

Targeting the Tinkers makes more sense by comparison. They wouldn't need such a big army against pacifists. I doubt the few guards the Seanchan had protecting the Tinkers would have saved them if the Trollocs reached them.