No
Skeeter,
I have no idea exactly what they test for, but DNP is not a narcotic or hormone based agent. Unless they are testing specifically for it, then there should be no crossover in the system. With that said, your urine is going to have a different color to it, which might raise a bit of a question, but most likely they will think it is due to vitamin intake.
Again though, DNP is not on a list as a medicine that you cannot take as far as I know. The only time the substance becomes illegal is if your sell it for the intention of human consumption. I might be totally wrong on this one, but even if they had a question about why it was in your system, I am not sure they would have a case.
The short answer to your question is: I have never heard of a single athlete who is tested for controlled substances to ever be popped for DNP in their system.
Hope this helps,
Kemo