I'm willing to bet that this is a case of very poor reporting on the actual nature of the lawsuit. It sounds like the F/A suffered both physical and psychological injuries from the incident but the Worker's Compensation Board (WorksafeBC) denied the claim due to a jurisdictional issue (as opposed to an actual denial of injuries).
The required next step for appealing a decision of the Worker's Compensation Board is a judicial review by the court.
While the event probably sounded more exciting to the journalist, they missed the entire point of the lawsuit - The the F/A claims the Worker's Compensation Board was wrong for denying her claim on a jurisdictional issue.
Briefly speaking, a worker is entitled to Worker's Compensation benefits if they are injured in the workplace (even if an employer is not negligent). So, if she was injured (both physically or psychologically) as a result of her job and/or an incident from her job. She is entitled to benefits. The determination of any injuries is made by medical professionals.
Just of note, although federally regulated, airline employees in Canada are covered under their provincial worker's compensation schemes.
For the record, I am a former lawyer and have represented both employees and employers at Worker's Compensation Tribunals.