I feel your pain. When I first came to MD (1999) I had to get my car inspected. I had tint on the rear and quarter windows. They said it was to dark and I had to pull it off. What a PITA!
What ticks me off about the MD inspection is that the price is different where-ever you go. It's not the same price at every location. And for those folks that don't live in MD the inspection is done by service stations, auto shops, etc..It's not at a State facility.
I think you just got an a**hole and I'd try elsewhere. I tend to stick to places in the country as opposed to the city.
I've had my car through emissions (which is a State facility) about 3 times and it's passed everytime with no problems. They don't look under the hood or under the car, just the sniffer and gas cap. BTW, I've put off my latest emissions test for about 2 yrs now:-) You can go online at the DMV and get a postponement.
Hope you get your car through. Good luck!