Please consider that even if your dog never ate a stitch of raw food, your dog licks his own genitals, ( including other dog's genitals), the floor, the wall, roadkill, ikkies outside in the grass... all kinds of things that are far more likely to effect a child than any raw meat will.
Frankly, it's a good practice to NOT let your dog lick your child's face, raw or no raw.
I really seriously doubt that raw food has anything to do with your child's runny stools. Dogs are dogs are dogs and have spend most of the lives picking things up in their mouths that we never will to tell you the truth!
In fact, that your dog will stop eating carbohydrates will actually serve to reduce
the bacteria growth in his mouth.