 Why had Betty really come to Ganymede?
The glowing semi-disk of Jupiter was more than half a million miles distant. It had been built for Ganymede, but not for Jeffers. He soon found that there was nothing for him to do but hang around the garage in case a spaceship should land. Sometimes there's no reason but them for sending a ship back with a crew instead of in an economy orbit. Under a portable, double-chambered plastic dome blown up outside the ship's airlock, a crewman helped him load two trunks and a collection of bags into the tractor. Trying already to be just one of the gang, instead of Lady Betty! They found they could send back loaded ships by 'automatic' flight—that is, a long, slow, economical orbit and automatic signalling equipment.
 to stay as long as it takes to discover who was behaving illegally
 to stay as long as it takes to discover who was behaving illegally  to arrest Jeffers for the crimes they knew he committed  to study how the business was run  to see if the real Betty could handle working there