The only trainers that are not teachers of Ravenwood are: Croaky (Digmore Station in MarleyBone). Sabrina GreenStar (Fairgrounds in the Commons in Wizard City). Mildred Farseer (Colossus Boulevard). Tish'Mah (Secret Island on Krokotobia). Niles (Krokosphinx)
Just to make it clear the teachers of the Death School and the Balance School are not considerd (SECRET TRAINERS).