Just speculation, but I think it was rendered with different software or least a different engine than what is normally used. I dont think it's AI. Blender instead of Daz if I had to make an educated guess. You can notice it with the animations as well the characters look quite a bit different in the stills before and after the animations. It was quite jarring for me, especially in the Reina scene.
There was a section about bad rendering in chapter 1 or something upon launch of the update and part of me wonders if it was meant for that section instead lol. I know the dev has had very unfortunate and difficult hardships with their eyesight IRL, and I pretty much attributed the few renders and farmers market segment to probably be partly caused due to those issues.
Could be totally wrong and it could have just been a crunch section because it has been
so long at this point since the last update and everyone was yelling from the rooftops that "this title is completely done, abandoned, never getting updated" yadayada that they just let it ride instead of redoing it. Which is also completely possible.
// on a different note //
Thought the update was fantastic, yeah the animated scenes werent top notch like usual but again genuine horrible IRL things to deal with like vision loss is one of the most legitimate reasons for someone to have problems developing a title like this. Still absolutely shines in every way in comparison to majority of AVNs, even for how much lesser-quality the animations were, they were still leagues above most. I got a couple great laughs from the banter & humor. I how consistent the growth of Artemis is, the writing didnt slouch at any points, it was mostly consistent with previous iterations. Also making good progression on the story and getting closer to the Expo. Honestly, was expecting 1/4th the update in content because thats kind of how stuff goes unfortunately, but I was pleasantly surprised and fulfilled with the release of a full chapter. Cant wait for the next one.