@Bantambird
you see the splash chick has a greyish /blue front head and the upper half of his beak . plus his hatch down is more of a washed up blue/grey rather than white with some buff and grey { silver chick do have some time a greyish white hatch down } like your chicks .
plus it is impossible that your Silver Black { Birchen } rooster will throw splash chicks .does not matter to what hen is matted to .
Splash will not come out of the black rooster /hens .
chooks man