Those numbers, by themselves, don't describe a fatal does of fentanyl, although they may have been a contributing factor to the cause. 11 ng/Ml is the average for a strong therapeutic dose, an average fatal dose is closer to 20 ng/ML. Norfentanyl is inert to the body, but may result from metabolized fentanyl.
The meth rates are a tenth of what is considered to be a fatal dose.