Why can't she just stay at Foundations? I'm not sure which grade she is in, but what you are contemplating does sound like a bit of school-hopping, which may (or may not) have an impact on your child. Imagine Foundations also provides an advanced/rigorous curriculum, right? The main difference is that CMIT is stem-focused. Also, in my view, unless your child is in one of the top-level classes at CMIT, the rigor and advanced focus, and teacher attention, won't be there.
Suitland High School has a performing arts program that requires an audition. That is an additional option. I may consider that school for my daughter, who is embarking on the dance competition journey herself. Good luck in whatever you decide.