Brown preferred to allow Trump a win on this one, or he risked being a loser in more ways than one.
Trump would have won on the NG to the border anyway, but Brown risked the embarrassment of Trump federalizing the CA NG, and that would have been a double whammy against Brown.
Which he already is.
Brown risked the embarrassment of Trump federalizing the CA NG
Could still happen. He might want to put a sock in it.