I've been hesitating to speak up, cos I know very little about children, insulin and toddler food.
But on the other hand, I know a heck of a lot about food, carbs, low carb and the various variables that affect MY body.
So (as I have read, and sympathised with your various issues) I have been wondering whether there might be food intolerances at play. The following is an example, based on my own personal experience. Please take it as that, and not any form of advice on what you do with your daughter.
carb g for carb g I can tolerate sugar better than starchy veg, and they are both better than grains. So 10 g of sugar does impact my blood glucose, but it is no where near as big an impact as if I have eaten 10 g of wheat.
So, in your situation, it would make my carb ratios and the consequent impact on blood glucose totally wacky - just as you are seeing.
If I were on insulin (which I am obviously not), I would have two options. Firstly map out a different carb ratio for different types of carbs. Or secondly ditch the wildcards, and stick to the carbs I
could predict. In my case that would be sugar, starchy root veg and non grains. All the grains (mainly the gluten containing ones) would be eliminated.
I do this 90% of the time anyway (minus the insulin) because I feel so much better without the spikes and dips that those grains cause.