While running around in the end, I've found a few end cities without ships. I saw another end city in the distance a couple minutes later and saw an end city ship in the distance. It was only there for about 2 seconds when it disappeared. My world seed is -872682677 and the coordinates for both cities are in the screenshots. This world is about 3 years old, so I don't know if the seed will work, but the world does have infinite generation on.