That was helpful. If her doc is suggesting she take time off, then do it. In the situation you describe, it would be non-negotiable meaning that if my daughter did not take it seriously, I would not pay for the sport anymore. I would get clarification on what she can do during her break - strength & conditioning but no tumbling or running? Is bar work OK? Or does the doc really not want her to do anything? Do you feel like the doctor understands the nature of gymnastics? If not, seek a 2nd opinion. What I would not do is try to find 'proof' from an online community that college gymnasts don't take time off because it was cited as an example by her doctor. This doesn't address your child's specific needs.
And really, if she needs to be out 6 weeks as more of a prevention - it ain't the end of the world. She'd be coming back with plenty of time for summer up-training and prep for the next year. You didn't mention her age but L9 and L10 are INCREDIBLY HARD on the body. The pounding adds up over the years.
To answer your question though - my daughter is D3 and trains year round. Her collegiate training is very different from JO training though. They try to limit overall pounding and seem to be more effiecient overall with how time is spent in the gym as far as numbers. It's not unusual for a coach or teammate to comment if they are doing too many numbers of a skill. There's also more emphasis on strength and conditioning. College students are older and their bodies have already been through a lot. My daughter in her first year learned more skills with less actual actual time on the apparatus than in JO.
My daughter also had a siginificant injury a few years ago (back stress fractures) which required frequent changes to the remainder of her JO training. Sometimes she had to take time off and often it was not at the best time but far better to rest than to 1. risk permanent damage or 2. or have to quit before she was ready because of re-injury.