Tuohy ran 15:07 a few months back on limited training. And she ran 4:26 in the mile, which was Ok. The 15:21 made no sense based on where people anticipated she was in her training. But hopefully it is just a bad race.
That said, injuries we know about aside, I recall that in the Spring on 2023 she started to struggle in training. She spoke about it and her coach mentioned it. The consensus was that she might be overcooked, kind of like Nico at NCAA outdoors. But in retrospect I suspect there might be something more too it. Injury, illness, overtraining, caloric, take your pick. But what happened to her at NCAAs was very odd. Time will tell.