Smelting can occur below the melting point of the metal, when the metal is still solid, but malleable enough to be hammered into shape. The temperature required for smelting is thus 300-400 degrees lower than the melting point. Medieval furnaces of 1000-1200 C were able to smelt iron.
I'm not actually disagreeing with you, though I may not be articulating it very well.
The good news is there's a ton of iron in Michigan, so it's likely this society will be able to find the good stuff in the Gogebic and Marquette Ranges fairly quickly once they've got basic metallurgy and bronze-working down pat. It's entirely possible that what you
really get is an extended copper age, followed by a brief bronze age as they get into arsenical bronze, then eventually using their knowledge of metallurgy to explore less toxic alternatives, like smelting iron and developing nickel-silver.
There's probably an offshoot of this culture in Minnesota; likely they find the Mesabi range, and you get a trade route that sees pack elk carry iron from *Mountain Iron to *Duluth, where it's loaded onto boats and sailed along Lake Superior to the other major settlement sites.
My heart, incidentally, wants the capital city to be at Sault Ste. Marie or thereabouts, near the rapids, or even on Sugar Island, centred around a big causeway connecting either side of the St. Marys River. Like some kind of First Nations Constantinople.
Incidentally, re. elk chariots: I actually think the main weapons for these guys are the bow and the javelin, with cavalry being basically unheard of. They might also use attack dogs. Swords, maybe, but they've still got elements of a hunter culture and they're more likely to want to kill their enemies quickly across a great distance. By the time Europeans arrive they're likely to find frightfully good Algonquian-speaking archers with arrows tipped with iron or nickel silver.