Curious because Federal Aviation Regulations require that a pilot wear a seat belt when at all times when at the controls of an airplane. The article says the "ejected" pilot was being trained in the plane. Was the other pilot a flight instructor? If so I see some serious issues here.
Also, even without restraints (seat belt) the mere loss of the canopy is unlikely to pull a person out of the cockpit. Were they performing aerobatics?
Certainly NOT enough information in this article.