He is a minor an subject to the zero tolerance law. The .01 is above zero. He can be charged. But, you are right, it is close.
Now, if you wan to fight the testing you will need excellent counsel and that counsel will need to hire an expert. The law presumes the test is accurate, your obligation to defeat that presumption. It is incredibly expensive. Here
is a link to North Carolina General Statute 20-138.3 regarding underage DUI.
What you can expect. It is a Class 2 misdemeanor
. He will get significant community service time (over 60 days), he will most likely be referred to an education program, he will lose his righ to a license until age 21. Because he is 17, he is not eligible for hardship driving until 18.
If you want to fight, get good counsel skilled in DUI defense. This is a link to the North Carolina Lawyer Referral Service
where skilled counsel with significant experience are listed and agree to offer a low or no cost initial consultation. This is a better source to look for a lawyer than a phonebook.