maybe because it doesnt exist any tested orgs? i dont know just asking.
There are some tested org's and i believe Layne has competed in them in the past, but i know APA rules and the drug testing isn't anything to worry about.
In this day of performance enhancing drugs it is very easy to get past a drug screen even if you aren't prepared for it. Drug testing is very expensive and most lifters will never have to worry about any sort of testing unless they enter a true natural federation.
I know guys who are juiced to the gills year round and compete in the same Fed's as layne and many other "naturals". I'm not trying to take anything away from the guy but he is so far from natural it is laughable at this point.
Either way he is still one of the top 220 lifters in the deadlift right now.