Shooting in mixed light at night creates choices for white balance. Below are a couple choices showing the differences of 1000k. Which one is right? As in most photography the right one is the one that looks right, in this case most natural. We all know the night skbrowy is black but blue also seems to fit into this reality. If in doubt I choose Auto WB and adjust until the colors look pleasing, a real scientific answer.
The best solution is to minimize ground light by shooting into a false horizon like a small swale or hiding the points of light with foreground objects.