I agree with Mick - I woudl not try to use WB for any correction to red traffic lights. If you look closely at a traffic light (the old ones not the LED ones) you'll see that it does have a bulb that disproportionately lights the center of the light. This makes the center brighter - and causes it to blow out in a photograph. It's an easy fix to change it in post processing.
The green cast that some see is only related to the LCD - not the image. I don't see a green cast, but some prefer a different view in their LCD. Don't change the WB, hue, or color of your images trying to fix the LCD unless you really know what you are doing. Technically, you might have a workflow that ignores those settings for RAW files so the change might not matter, but if you ever shoot JPEGs without resetting the color you will have images that are off rather than just an LCD that is off to your taste.