I think her parents should instead focus on a school that will broaden her horizons. It may be that she focuses on anime because of her HS experience. It would not benefit her to miss out on other activities in college because she remains stuck in her HS mode. Living in the Midwest gives her great opportunities at many top tier large flagship U’s- perhaps even instate for her. These large top notch U’s will have large enough student bodies to include those with her anime interests.
Again, I strongly suggest her parents encourage her to look at schools that not only will have like minded students but will also have ways of expanding her horizons. I know of many gifted students who struggle socially because they do not have the peer group they need in HS. Plus their innate personalities do not fit the typical HS student. It could be partially that she is an introvert in an extrovert’s world (years ago a conference I attended as a parent stated 75% of the population is extroverted- a spectrum, btw- while 75% of the highly gifted are introverted). Harder to get social cues when different.
Finding her “tribe” would be easiest at a flagship where many top students end up in honors programs plus a large enough student population for her interests. Think overlapping circles/Venn diagrams. There will be no schools that are a total match but many that include various aspects of who she is. Also, in college it does matter what the majority does, just that you find a few like minded peers.