Is @scholar.social somehow blocked from #qoto?

I was surprised to find that I can't tag colleagues like Sarah Eaton (@drsaraheaton@scholar.social), and none of her tweets show up when I look for hashtags she recently used, like "AcademicIntegrity (today)" or "PaperMills (Feb. 15)".

Did I misconfigure something?

Some enlightenment would be much appreciated. Thanks!