i had no idea how to tag this, because based off the genga uploads at https://www.sakugabooru.com/post/show/87837 and https://www.sakugabooru.com/post/show/87838 we know the majority of it is him, but the few cuts that don't seem to be included at the start and end of the scene aren't confirmed. even though im almost certain they're him too, i am under the impression a presume is still necessary because of those, if they arent hard confirmed

edit: turns out i was right to do that, sushios atwiki page says he did the parts where the "classmates gather", which has to be the bit at the end here https://w.atwiki.jp/sakuga/pages/228.html