I would not double sire a DH clutch with the two different recessive males in your case because your KillerBee Axanthic is only a Het.
Pied x Axanthic clutch would look all Normal.
KillerBee Het Axanthic x Axanthic clutch could contain Normal looking babies.
How would you know what the Normal looking hatchlings are? They could be DH Pied Axanthic or 100% Het Axanthic. Not a good scenario.
It is quite different than siring a clutch with a Black Pastel 100% Het Pied and a Pastel 100% Het Pied x Pied..... you know those Normal looking hatchlings are all 100% Het Pied.
Your scenario, if I understand it correctly, would leave some hatchlings you would not really know the genetics of without proving them out years down the road, and therefor not really able to be sold as much more than Normals.
I hope I understood your question correctly??