A presidential press release stated that the offer did not violate ethics laws because the job offered was a non-paid position.

That statement was an admission that the offer was, in fact, made.

Lawyers who have read the law point out that the salary (or lack thereof) is not even mentioned.

It's the offer that is a crime, even if made through a third party (here, Clinton).

Obama is (most likely) in no trouble because he is an expert at making the decisions and then putting distance between himself and the consequences.