Degus can get along with well with some animals, but they can't live with most animals because they need special food and if they would eat for example food of hamster or a rat, they would very probably develop diabetes or liver problems and won't live so long as healthy degus. And of course, you can't tell degus not to eat from other animal's food dish.

The only animals who have similar food needs are chinchillas, guinea pigs (cavies) and rabbits. With them degus also usually get along well. You must try how they'll behave but very probably they'll become friends.