Yes. The cheer squad should have gone on without her. No reason for everyone to stop what they're doing while the one diabetic in the group takes care of herself.
The fact that she needs assistance is not the issue. The fact that she apparently has not done anything to ameliorate the day-to-day problems and still has extreme needs that stops what everyone else is doing is the issue.
I had friends while in school (and still have many of them to this day) that would have died of embarassment if the world stopped every time they needed to take care of a recurring medical need, including diabetes. And - like it or not - not everyone can do everything. My hemophiliac friend would have loved to have played football while growing up (and to this day), but there was no way he could do it and not absolutely disrupt everyone around him so he could be accommodated.
If the activity was too much for the diabetic cheerleader (and one of my high school friends had to drop out of the track team because no matter what she did, she had severe swings and issues after the exertion of track practice and meets), then she needs to find an activity that does not recur an ambulance to follow her around. I have terrible knees, and really REALLY miss cycling, but the Tour de France is not going to switch to race-walking just for me.