Are you saying that the grass there was green prior to you putting down the corn gluten meal? I don't see this as possible. Even if it had some pre-emergent properties, I really doubt that it would have an effect on grass that sprouted last fall. My guess is that the problem is due to something else.

Could it be a temporary nitrogen lock as it starts to decay? If the color improves radically over the next three weeks, that would be my guess (but only a guess).

or you smothered it.

We'll see how this little unintended experiment plays out. It definitely wasn't smoothered bestlawn.

I grew up on a farm, and we used to use use Treflon on our cotton. Now, of course, its supposed to keep the listed weeds from sprouting but not hurt the cotton. But, if you got too much of it, it would kind of root prune or stunt the cotton. I don't profess to know the biological actions involved, but, I've seen it many times.

My guess is whatever chemical/biological action the CGM has as a pre-m, it had on the new seedling still trying to get rooted in.

Of course, that is all just guess work. Its definitely more on the yellow side. Otherwise treated just like the rest of the yard that has both KBG and fescue areas which are green as can be.

If you water the baby grass area, no amount of CGM will harm it.
CGM works best on the youngest roots, it inhibits their ability to hydrate the plant. Frequent watering defeats that purpose.
Not implying that you water frequently! Just giving the condensed version of how CGM works and let you know it can be counter-acted upon by watering frequently, if you must.

Thanks for the heads-up Barb. Good info.

Out here on the high plains, keeping it wet in a shallow root zone of new grass can really be little hard, even with a system. So, it was probably needing a little more than I have been giving it.