1995 BMW 525i Will not pass emissions

Hello, I have a 1995 BMW 525i, it will not pass the Nox portion of the emissions test(AZ). It's supposed to be 2.0 or lower and I've been hitting 5.0! I had the Catalytic Converter changed and now it's even higher! 5.60! Tonight I found a hose that leads from my air filter to the engine and there are 2 big holes in it. Can that be the reason it is failing? And what is that hose? Thank You so much for your answer.