Looks like your situation is similar to what we have here in Colorado. Chumming (pre-baiting) is illegal. "It is illegal to introduce anything into waters of the state for the purpose of attempting to attract fish (e.g. chumming, artificial light, acoustic equipment, etc.) that is not attached or applied to a lure as defined"
"A lure is defined as any man-made object comprised of metal, plastic, wood and/or other nonedible materials made or used to catch fish." So, if you use a method lead, or popup boilie rig, etc., you are fine as long as the bait it attached to the lure.
Some here in Colorado question the use of pack baits and there seems to be some discretion among wildlife officers whether that is considered chumming. I do not consider it to be so, since I embed the hook in the packbait, and it remains attached by a hook link the entire time I am fishing. The packbait does tend to dissolve a bit and float around, but it was attached when I cast it out. An officer may disagree. I don't know, I haven't spoken with one.
North Dakota regulations define bait in three categories: 1. Live bait and baitfish, 2. Terrestrial bait (such as nightcrawlers, and waxworms), and 3. Manufactured bait. "Products manufactured as edible fishing bait and other inert biodegradable substances are legal bait."
Corn is not specifically manufactured to catch fish, but would certainly seem to fit within those definitions. It is certainly not prohibited. Same with bread, oats, bread crumbs, or other substances often used in carp fishing. Not specifically allowed, but it's hard to see a wildlife officer complaining about corn when nightcrawlers and salamanders are expressly allowed.
As always, your mileage may vary. Game officers are very individual and may have their own definitions, especially for a species unfamiliar to them, such as carp.
Another thing to keep in mind though is that the North Dakota regulations define common carp and silver carp as None-game Class III Aquatic Nuisance Species (ANS), which "can be kept for consumption if legally harvested." but "cannot be released alive back into a waterbody after they have been harvested." So apparently, catch and release carp fishing is illegal in North Dakota.