Lots of debate about rust inhibitors. It doesn't hurt. There are many frames that have endured decades of abuse without the inhibitors. Your frame won't rust out on this trip. But, you do live in Chicago where they salt the roads, so it may not be a bad idea if you ride in the winter.

You will grind down the tires quite a bit in 5000 miles. If you rotate them once or twice, most quality pairs of tires should survive the trip, but it might not hurt to have a replacement plan in mind. I don't think I've been stuck beside the road due to hole that is too big in a clincher tire. I've had a few flat sewups in my life, but even those holes were also typically small.

I have started carrying Park Boots. They are easy to carry. About 2x as big as needed (so far). If used as a long-term repair, they will eventually chew through a tube (1000 to 2000 miles). There are a lot of DIY boots that may be just as effective, including MONEY.

Even if you finish the trip on the original tires, you may be ready to replace, so a set of spares at home isn't a bad idea.

Foldable tires are easier to ship and carry than wire bead tires, with no real benefit of wire beads.

As far as the chain. If it is dry, it may well last the whole trip. If you hit a lot of rain, you could wear out a couple of chains.

Like the tires, have a replacement plan. Most quality bike shops should carry the spares. Or, if you know where you're heading call ahead.

Heck, you could also wear the brake pads a bit depending on your riding style, but they won't leave you dead beside the road unless you really neglect your maintenance.

Did you discuss where you're staying? There are likely a few BF members what would hold supplies until you pass through, or give you recommendations of places to shop when you come to town. And, may even loan you a couch for a night.