There are softwares already which can generate AI arts so I think this one should not count because if they allow AI arts for sure many participants will enter and just go with the software so that it can generate them an art without putting to much effort on it. That is so unfair to the participants who spend to much time to their arts creating manual arts or even hand written ones.
They can participate, but the probability for them to win is very low because with Roobet art contest, there's a lot of good participants and most of them are digitally hand drawn and carving something into the best art. The team of Roobet knows this for sure, so we don't have to worry about that software or if they won using other's picture or art, then we can raise that concern into the right thread. Few days left before the end of the new contest, better to focus on that.