I see y'all have cut to the chase.
I think that once y'all have agreed that corn meal and corn GLUTEN meal are both legitimate fertilizers, then this issue of can you apply it as a anti-fungal (in the case of corn meal) and/or a preemergent (in the case of corn GLUTEN meal) is a key concern on this forum.
I would suggest this if you believe you can do it. Apply corn gluten meal as a fertilizer in the spring and fall. Apply corn meal in the summer. If your season is long enough to work it on a 90 day cycle, then that's how I would do it. If you get a week of steady rain, you might offer a second app of corn meal "to fertilize" but really to control any fungus that might pop up. You can apply corn meal in the rain, by the way. Kinda messy but duh. I'm just saying nobody will get hurt and the grass won't be hurt.
Every organic material you apply is going to have the long term benefit of enhancing the health of the beneficial soil microbes. Organic materials also enhance the ability of the soil to prevent disease. Some just do it more efficiently. Does that make alfalfa a pesticide? -even if it is a fertilizer?