I had the same problem here when I went for my emissions test several months ago in Boulder. I stopped by Pollard and they swapped out my 35s for a set of stock wheels and tires so I could go run the test. Bit of a nuisance, but they only charged me a minimal fee ($20 or so), and it got the job done....until next time.
Personally I call BS on requiring a test then turning people away for being "incompatible" with testing equipment. And for 35s, most of which don't actually measure a true 35 inches?!?! Lame.