We just about never had a dental procedure animal stay over night. Cavities are rarely filled in dogs, I suspect the teeth will be extracted.
Issues in dogs this young sometimes reflect a problem during the development of the teeth, way before they erupt. Sometimes fever, medications, diet will make the dental development abnormal resulting in defective weakened enamel.
As far as sedation/anesthesia at this age, I understand the worry, but a healthy animal at this age is in the best shape of his life and is better able to handle this procedure. My advice, keep a reasonable perspective about potential problems.
Doug, DVM