Give the chick the coconut oil and the gro-gel. Do it immediately. I use the coconut oil in its solid state. Chill it if it's liquid. I slip tiny bits of the oil into the chick's beak until I get half a teaspoon into it.
Your brooder is much too small. The bare minimum size, even with chicks this small, would be around two feet by three feet.
If you can find a thermometer, place it on the floor of the brooder right beneath the heat lamp. It shouldn't be over 80-85F. Then place it farthest away from the heat footprint. It should be considerably cooler. If the brooder is all one temp, the chicks can't shed excess heat, and that will make them sick, and they could die if they are overheated for too long.