I have worked with Z chromosome-linked mutant genes in pigeons and ringneck doves.
If banana/coral glow was a routine type of Z linked recessive mutant, then a b/cg female mated to a normal male would produce normal females and normal looking, het b/cg males. So b/cg is not recessive to the normal version of the gene.
If banana/coral glow was a routine type of Z linked dominant mutant, then a b/cg female mated to a normal male would produce normal females and b/cg males.
Whatever is going on in the chromosomes seems pretty weird to me. I still have to look at that fish paper, though.