A good german Shepherd pup should be prey driven. If you don't have the time to properly manage one then it's probably best to rehome. But don't blame the pups for doing what comes natural to them. It's your fault! At 5 months you can't even get them to sit still much less stop chasing game. It is weird when you see your cute pup kill another animal though. When my pup killed a rabbit and was eating it's intestines, I wouldn't let him lick me for days!
If you're fed up because 5 month pups don't understand to leave things alone that they were born to chase then yeah you should rehome. Most definitely not the right dogs for you. And why you would get 2 at one time is confusing?