This is very philosophical question, why random generator in artist mind is something different from random generator inside the AI. We don't have scientific non-falsifiable method to verify what is 'intention' inside some process, let it be human mind or 'AI'.
But for legal point of view or practical search purposes this philosophical question is not important.
I can write script which reuploads back to to derpi random mirrored image from derpi. Technically it is the same, script generates new picture withot 'intentions'. I can do a little bit more sophisticated transformation than mirroring and mix features of many pictures. When the program mixes features of Fluttershy with features of Fluttershy, it gets Fluttershy, not "new character".
Also, it was AI generator developer intention, to take existing characters into training set.
Also, artist can use random dices to randomly select pictures from derpibooru to mix them. There is no difference if program roll dices.
If I totally randombly choose pictures to trace and features of some random character, it still will be trace of one picture with features of this some character, which can fall under DNP of original artist. If some program perform this trace, it causes the same results.