You can only mix & match and reuse genetic stock for recreating new hybrids up to a certain extent.
Sometimes you run into genetic dead ends such as sterile offspring. That is just how the genes play out.
This genetic dead end is sometimes desired by other sectors in the scientific community - such as a project to develop a process to cause future generations of a specific crop pest to be sterile, and thus causing the species to be eventually extinct. Such a powder keg that was.