The fire never reached the basement. Why is the basement in the restoration scope?

Because the water did. Suppression sends hundreds to thousands of gallons into a structure, and gravity delivers them to the lowest finished level, down stairs, chases, and the garage wall, where they sit in wall bases and floor systems while the fire floor gets the attention. Left out of the drying scope, that water becomes the mold and odor chapter of the same claim, weeks later and argued as a new event. Reading the basement with meters on day one, and drying what the readings condemn, is not scope expansion. It is the same event, finished.