hey are all het amel, anery,i think het zigzag/aztec, and possibly het motley/stripe LOL
I haven't seen any motleys or stripes in there. As of yet, there's no proven correlation between odd belly checkering and being het for motley. There's no reason right now to assume they're het or possible het for motley, or stripe.
As for aztec, I don't see it at all. Minor zigzagging, yes, but not aztec.
There was a recent post where people posted a bunch of what I call zigzags, and they called all of them aztecs. I was scratching my head. It seems that most people have a very different opinion of those two terms than I do. IMO Aztec involves breaking up, or "shattering" of the saddles themselves, where zigzag is simply an offset from right to left, making the zipper pattern like you've shown in the latest hatchling.
To me those are two extremely different looks, regardless of whether or not they are caused by the same "gene." If they aren't different, I don't see what point calling anything an "aztec." 
Anyway... some appearance of zigged saddles can appear on some offspring, even if neither parent is "het" or shows any signs of it. If it appears on one of the parents, it might be safe to assume that those also showing it are "het." But there are obviously more influences to zigzag than a single gene... getting near-fully zigged corns requires selective breeding.
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Useful stuff on the Serpentine Widgets website:
Morph Library
Genetics and Inheritance Tutorial
Snake Measuring Program
Cornsnake Glossary