I agree with others that looks like a rooster. Still very young, not too surprised there's been no crowing or breeding attempts yet, if it does turn out to be a rooster. Just because a bird was in the nest doesn't automatically mean IT laid that very egg. Could be just sitting in there or was taking refuge from the banty roo.
It's an EE. The reason you didn't find one that matched is because EE often are deliberately mixed very freely as to color or even breeds. So there are going to be EEs that don't exactly match colors or even appearence to anything. Most EE have a beard and a pea comb.. and it has both.
All three pictured in this thread are on silver and columbian base, only the second one happens to have extra genes that clean up the white on body, the other two lack it so the pattern is more varied. It's a result of random breeding & crossing.
An example of clean silver with columbian pattern are light brahmas.