Basically all states have this type of law on their books. Enforcement varies.
He was not working for pecuniary compensation. This was not gainful employ, but an individual pursuit. Had he not mentioned qualifications which have not been registered with and approved by the State, he would have been fine, and ironically, his results would have been something he could have published at will.
I am a licensed, registered Professional Geologist in the one State where I am likely to work that requires it. I have noticed how the laws there have become more intense for those who are not already in the club, so to speak. Every year I pay to renew that license whether or not I use it, because being reinstated should I need to do so would be prohibitively time consuming and expensive.