Elliot,
Maybe I’m fortunate, but the TREs and TRIs that I deal with. both from the airframe manufacturer and customer airlines tend to be both knowledgeable and very critical.
Like you, I also deal with many authorities and again I find them to be generally pretty good.
Simulated malfunction acceptance is a bit more in depth than "does the malfunction do what the button says it will do?" In the initial phase of simulator production a Malfunction Definition Document and Acceptance Test Manuals are supplied to the end user for approval. These documents detail exactly what the malfunction is and exactly what characteristics simulated systems will exhibit. On more modern simulators this Malfunction Defn Doc is even being linked into the Instructors Station help system. This ensures that the instructor knows just what the malfunction will do. (On older devices it’s unfortunately still a paper exercise).
I too wish there was greater standardisation, not just malfunctions, but across a far broader simulation spectrum. Trouble is that different airlines/Fleet Captains have different requirements.
I don’t entirely agree with your comments about local techs and local support. From my experience once a simulator has been in service for a few years, the local sim engineers tend to be far more knowledgeable about their sims than the manufacturer. Of course the standard of maintenance is dependant upon the resources made available to the sim engineers, but that’s another ‘beancounter’ story………..