I honestly don't think it's crazy to suggest a fecal regardless of how much information there is. Your right, the OP never said adult mouse, but fecal exams should be part of standard care. It's usually recommened that you get fecals done every 6 months if you are feeding live and every year if you are feeding f/t. It is never crazy to suggest a fecal exam regardless of how much information is supplied. They only cost ~$25 and then you can say for sure his slow growth is a direct result of his feeding schedule. Most vets should be willing to do a fecal exam for you without seeing the snake, so I don't see why having numbers to give to the vet is important.