You/your friend needs to get an x-ray ASAP, even if that means going to a standard vet. You cannot get a diagnosis online, and any advice will be guesses at this point. This should not wait until he can get around to it, seeing that vets will likely be closed if he waits to pick it up until this weekend, so the poor snake is now waiting until Monday at the earliest for the help it obviously needs. You'll need to tell him exactly when the swelling started, and the dates for the feedings, along with all husbandry info to provide the vet.