If she was in preteam at age 3, she was probably being prepped for a competitive level that more serious gyms might not even compete.
At my daughter's gym preteam starts at 5-6 years old and they are prepping for level 4. If a 5 year old came with 2 years of experience in preteam it may not matter at all, and may be a disadvantage if they were not primarily focused on flexibility, shaping, lines, straight legs.
The girls on my daughter's preteam are not put there because of skills. They are selected for strength, flexibility, body type, and coordination. A girl with more skills but who lacks these other attributes would be passed up. If they are a gym
that only takes girls that can plausibly make it to 10, they may have decided your daughter isn't their type. They may be incorrect in their assessment, but they may have made their judgement on something you can't control. A more inclusive gym may be the best option for her.