Your last sentence is completely a stunner. Your 15 year old is nearly an all A student and got a 5 on AP Chem last year as a freshman.
An A- in an AP class to derail her? Seriously? Nothing guarantees her admission to a BS/MD program. Stop chasing that. She needs to present herself as having resiliency and self drive. With your hovering, I doubt she can develop that part of her character. What’s driving all this? What does she want to do? While it’s OK to overwatch a kiddo’s progress – you may be seriously creeping into “tiger mom” territory.