I used to be a long distance truck driver and got popped with several randoms by the company I drove for. Just my experience, DOT used 5 panel test kits each time. But like u I was too chicken to smoke in that period. DOT don't observe while u piss so u should be ok with fake piss so long as u have a plan for concealment and heating ur sample.Wish I could tell u more, but that's the extent of my knowledge. I'm seeking some info on detox time myself. Good luck!