K & M

AOS is discretionary, so there's always a chance it won't be approved. However, they won't deny it solely for preconceived intent, even if they can prove the intent. The Battista case in 1987 put a stop to that. Battista succeeded in getting an AOS denial overturned because preconceived intent was the only reason it was denied, and the BIA determined that his family ties in the US outweighed that one negative factor. Since then, USCIS doesn't deny solely for preconceived intent. They will deny for material misrepresentation if they determine the applicant lied about their intent to an immigration officer, though.
In your case, I doubt it will even come up. First, your wife is not from a high fraud country. Second, she has been lawfully present in the US for years. She made a brief trip home, and reentered with the same visa, essentially just continuing her previous stay. If an IO was going to apply the 30/60/90 day rule then they would have to set the WayBack machine to 2007, because that's when she originally entered with her J1 visa. If they were going to suspect her intent for any reason then it would be because she returned with only a couple of months left on her visa, and not because of when she married. She could have married a long time ago, if that was her real intent.