 Who betrays Retief? How and why?
"Whaffle left here three months ago," Retief said, "leaving me in charge." "Mr. Retief, those are just the sort of questions we avoid with the Groaci. "The impossibility of access to outworlders. Outside, Retief stood for a moment looking across at the deeply carved windowless stucco facades lining the street, then started off in the direction of the Terrestrial Consulate General. Retief went in. He looked at Retief and froze in mid-motion, a metal tube poised over a waiting pot. "To enjoy a cooling drink," Retief said in Groacian, squatting down at the edge of the pit. "To not worry," Retief said, irritated. "To get the lead out," Retief said, placing a thick gold-piece in the dish provided. "To not be angry, fragrant native," Retief said. Retief backed into the opening to a narrow crossway and offered further verbal familiarities to the drunken local, who followed, furious. Retief backed, rounded a corner into a narrow alley-like passage, deserted, silent ... except for the following Groacian. Retief stepped around him, seized his collar and yanked. Retief stood over him. The downed native half-rose; Retief put a foot against his chest and pushed. Two Groaci wearing heavy eye-shields and elaborate crest ornaments indicative of rank rose as Retief entered the room. "I wash my hands—" "Just keep that recorder going," Retief snapped. "I'll not be a party—" "You'll do as you're told, Miss Meuhl," Retief said quietly. "You reopen an old wound, Mr. Consul. "All our efforts," Miss Meuhl said, "to live down that terrible episode! Fith rose; Shluh followed suit. Were it not for your diplomatic immunity, I should do more—" "Why did the government fall, Fith? It has outdone itself—" "—to keep the Terrestrial consul and his staff in the dark," Retief said. "I can talk no more of this matter—" "You'll talk to me, or there'll be a task force here in five days to do the talking," Retief said. "Answer me this one," Retief said, looking at Shluh. After being securely caged, they were exhibited to the gentle Groaci public. "Did you murder them, cut their throats, shoot them or bury them alive? "We'll deal with that question later," Retief said.
 Miss Meuhl. She reports Retief’s espionage to Groacian officials. She does this because she believes Retief isn’t acting the way he should as consul.
 The previous Consul, Whaffle. Whaffle confesses to Groacian police that Retief broke into the Archives and stole information about the missing cruiser. Whaffle did this because he wants his old position back.  Miss Meuhl. She reports Retief’s espionage to Groacian officials. She does this because she believes Retief isn’t acting the way he should as consul.  The crew from The Terrific. They have been in cahoots with the Groaci the entire time, and are dead set on betraying the human race in order to find financial gain on Groac.  The Groacian bar tender. He believed Retief needed to be beat up by the drunken Groacian.