Female ejaculate actually comes out of the Skene’s glands, not the urethra (and of course not the vaginal canal itself, either). Last I checked, researchers were not sure exactly what it is or why it is produced, but they know that it is definitely not urine.
There is also no controversy regarding the existence of female ejaculation. You can find many, many videos from many, many different women if you haven’t researched this topic.