I think the thing about protein and fats reducing the impact of carbs is only useful if there is something with highish carbs that you would like to eat without causing too much damage to your blood sugar levels.
I doubt that eating more carbs, no matter what you eat with them, is going to be an effective way to lower you Hba1c.
Using a meter to understand exactly how your food is impacting your blood sugar levels is really the only sensible way forward.
When you have collected enough of your own data it becomes obvious what you personally need to avoid. With the help of your meter you will become the foremost expert on your blood sugar