Sr year is a scary time in a kid's life. So many unknowns ahead and most start to become aware that the clock is ticking till graduation and this in itself causes stress separate from the what will I study, where will I go questions.
I quoted the part above because it seems like you contradict yourself.
What you describe as her frustrations - the injuries, the stress and worry of 'keeping up' and maintaining a certain level of performance so that she can be competitive at her level -- I hate to be this blunt, but that IS L10. Even if she is healthy and able to compete all year, the stress and worry will still be at play. I'm inclined to think based on all that you've shared that she may know exactly what she wants regarding retirement from gym.
I think it's a good idea to visit the schools. I agree with
@Madden3 that 8 will be overwhelming. Given that she's unsure about gymnastics, I would also suggest that you don't make the entire trip about visiting schools with gymnastics programs. If she hasn't already, she should visit some schools that she is interested in that don't have gymnastics. I also like the advice that
@John had regarding parental desire.
I'm sorry if I'm coming across as harsh. No judgement here as I can relate to your post. I'm a year behind you in the college process and my DD will be lucky to hit L10 for her senior year. She would like to compete D3 but is realistic that it may not happen. Lately she's had some crazy, exciting ideas for college. It's not what I expected from her but I'm embracing it and taking her lead as she explores. As others have mentioned, club gymnastics could be another way for her to stay involved in the sport. Or she could coach and/or become a judge.