I am curious if he tried the same at Tesla or SpaceX: "Hello dear mechanical engineers, please bring photos all the cars/rockets that you created in the last 6 months".
If you're still on HN and you can hack, head to YCombinator's HQ. Bring photos of all your hacks from the last 6 months.
I would think that would work rather well, since it is 100% visual.
I'm not that type of engineer, but I suspect it would be much easier as well. An ME could just show a picture of whatever part he designed. If it's part of the car's running gear it is unlikely to be something un-needed. If that person was an EE, they could just show a picture of the wiring harness potentially if they built that. The car is basically just a static display without that.