Your wife does not want to admit she had the immigration intent before she planned to enter US using B2 visa, does she? If yes, she can be considered to have fraud during the B2 visa application which probably results in a serious problem. So, the principle is that the CBP officer considered she has immigration intent because she did not convince the officer, not your wife admitted she had the fraud. So, the only consequence is that she was not allowed to enter US at that time, no other negative effect on the immigration visa application because the CBP officer just thought your wife had immigration intent, but not verified it (they do not need to verify it because it is difficult/immpossible for them to do that, but it is simple just to refuse your wife admission into US).
NVC or the US Consulate will not care about that issue as long as your wife can explain it (actually the Withdrawal of Application for Admission/Consular Notification has clearly showed the reason).