 What is the role of the Saarkkadic people in this story?
Somewhere out there, the ships of Earth were ranged against the ships of the alien Karna in the most important war that Mankind had yet fought. The Saarkkada themselves were humanoid in physical form—if one allowed the term to cover a wide range of differences—but their minds just didn't function along the same lines. To violate the rigid social setup of Saarkkad would mean the instant closing off of the supply of biochemical products that the Saarkkadic laboratories produced from native plants and animals—products that were vitally necessary to Earth's war, and which could be duplicated nowhere else in the known universe. Not the worst ones, of course; there were places in the galaxy that were less important than Saarkkad to the war effort.
 They produce some materials important to the Terrans.
 The other races are vying for attention from them for support in the war  They are overseeing the peace talks.  They produce some materials important to the Terrans.  They provide a place for Malloy to hide from his own people.