I also gave my chicks fermented chick starter right away, and they love it!
I have what I guess Milliefleur called a whole grain starter. It contains different sizes of ground grains, very fine to just sort of cracked. So they get a variety and the soaking/fermenting softens the larger pieces well. The first day (they arrived) I gave them some of the more mushy sediment (the fermented finely ground bits) thinking the others were too big and they loved it. But the next day I did give them the whole mash and they gobbled it up no problem. I gave them a tiiiny bit of grit in case they needed it for grinding, may not have been necessary. They are doing very well, they also like yogurt a lot (one in particular).
So in conclusion, I agree the common chick starter which is very fine can still be fermented, but it will be pretty wet when given to them.