The composition and positioning come from the original seed. If the same seed is used, the same background image noise is applied for the initial image which is transformed into all the styles.
Thus the similarities you see would make sense if using also the same seed for the tests.
Yes, if you generate a bunch of images of waves or the sea, or other repeating patterns with the same seed, you can see how all the 'peeks and toughs' of those patterns line up in the same place.
Thus the similarities you see would make sense if using also the same seed for the tests.