There was no operational protocol in the Odunga administration. Comey already proved that by usurping Lynch’s authority. So it’s not a stretch Brennan stepped out of bounds as well.
Here is an article explaining her multiple entries into the US. Lynch signed off on the first probationary visa and then the work related visa would have gone through DHS and State. According to the article, the work visa was fishy because she didn’t speak English.