I can't speak for the yet to be board of directors of HEPAC, but I can say from my own knowledge and have posted it on other threads, that all contract pilots or engineers should carry liability insurance.
For every action there is an equal and opposite reaction, depending upon the circumstances. (this just redefing Bernulli's principale).
Liability means somebody or something is responsible for the cause of an accident. Defining this is something else. If it is an engineering problem that person or manufacturer is responsible. If the aircraft capabilities or the pilots capabilities were exceeded and caused an accident, it is reffered to as pilot error.
In actual fact an engineer or pilot causing an accident through there own negligence can be sued by, the insurance company and or the families of the accident victims and or the company they are employed with.
As far as fraud is concerned, I don't know if I answered your question. Stupidity or negligence does not have any years of experience or flight hours attached to it, it can apply to anybody.
As far as TC getting involved, I doubt it, unless something is obvious.
Normally in Canada if you take the time to check on a persons resume, you can, as the person doing the hiring, find out every thing from the day they were born.
So, in retrospect, no excuse.
Last but not least, an engineers capabilities will show up on the hangar floor and a pilots capabilities will show up in an extensive interview and check ride.
IMHO
Don McDougall