Have you aerated the corn with a hoe in the rows and some tilling [if rows are wide] between to open soil to air and drying?

It's hard to say about the nitrogen. I specialize in good drainage to prevent your problem.. I also mix in some slow releasing organic fertilizer in the row before planting that likely will work all season.

Take a look. Is it poor drainage or nitrogen?

I'm concerned.

If the ground had standing water, it is likely a drainage issue. Corn without any nitrogen fertilization should not look that yellow and peked.