I am a little confused about your teminology-
Veil implies one veil gene
Superveil implies two veil genes
double dark implies two black genes
black lace implies one black gene,
So when you say "double black lace"... it cant be both- either the fish has two black genes, or one black gene which is dominant over some other patern- which can sometimes still be seen as a darker black pattern under the primary black, which is where the name black lace comes in. So which is it?
Either way all the fish will be appear black if at least one parent is a double dark. If both are double dark, 100% of the offspring will be double dark. If only one has both black genes, and the other is a black lace, the babies will also be 50/50 double dark/black lace
and if one parent has one veil gene and the other does not, then 50% of the babies will be veils, and 50% standard fin.