Yes, in Ohio (and I think also most other approved states with a ginseng management program) it is not lawful to possess uncertified ginseng during the closed season.
I understand it was an oversight, however, it is also a legal requirement that diggers must keep records of their harvested ginseng by the day. So essentially, the fact that he forgot about it indicates another legal issue.
I'm not trying to be the hardass here, just precautionary and offering friendly advice. Were it me who found out within my jurisdiction...you bet I have other things to do. However, a stern warning is certainly in order. But that is me. I have been a cop long enough to know that I'm a little more understanding than some folks wearing a badge.
...and I think if you get them in the ground ASAP, they will probably be ok in a year or so