There is already a draft ball genome out there. It is not annotated though, and I am not sure it is fully scaffolded…
But yeah, just having the base genome is not enough, you would have to find the locus for every major morph/complex. But as @chesterhf said, that takes $$$
And then what do you do with all the info?
Once you have the loci, you could set up a real simple PCR panel to test for het status on things, but I am not sure if that would really be worth it in the long run: I do not see breeders spending hundreds of dollars to screen poss hets to find out which are or are not just so they can sell them as 100% het, it would be more economical to just sell them as poss hets.
The only other place I could see it being useful would be for clearing up things like allelic complexes, but even then, we already can do that way cheaper. Are Spider and Spotnose actually allelic?? Run the PCR and find out… Or just make the Blackhead/Spotnose combo and bred it out a few times and see if you only get clutches of Blackhead and Spotnose but no combo and no normals.