Fantastic results and good pics.  I’ve done restoration of natives all over our four state area but without the possibility of spray of any kind. All on right of way restoration for municipal operations.  My main source of seeds is roundstone native in Kentucky. They are very knowledgeable and has had anything I needed.  Most need to be planted in winter and very shallow so stratification can occur and they be ready for spring, unless you find a source of Artificial stratification .  Some will come up anyway but most need to mimic the natural seeding on the prairie. As expensive as they are get the best source you can find.  I just did a municipal job that the engineers designed a seed mix that added up to over $4,600.00 per pound and there was a few non native flowering varieties in the mix. Bean counters never flinched a bit .