John, I think your confusing the concepts of wild and native.
I didn't want to have to go to the dictionary, but ...
Wild:
–adjective
1. living in a state of nature; not tamed or domesticated: a wild animal; wild geese.
2. growing or produced without cultivation or the care of humans, as plants, flowers, fruit, or honey: wild cherries.
Native:
–adjective
1. being the place or environment in which a person was born or a thing came into being: one's native land.
2. belonging by birth to a people regarded as indigenous to a certain place, esp. a preliterate people: Native guides accompanied the expedition through the rain forest.
A lot of folks use the terms interchangeably, but they're different. Wild means they've been out of the hatchery long enough to adapt to their environment, i.e. learned to find food and avoid predators. The term is commonly used when describing these trout (NFOW rainbows) because they behave differently than trout fresh from the stocking truck. And, that's a distinction that's important enough to warrant being called 'wild'.
I use the term stream bred too -- it's a little more specific than wild. But wild is wild, and native doesn't fit any trout swimming around in the midwest.
As to your DNA comment -- well, there have been DNA studies done, on Crane rainbows at least, and they're pretty confident there's no 'stocker' in them. They're extra special in my book.
Again, rainbows in NFOW, BSC, Mill, Crane, etc. are wild -- by definition.