Second, had there been organic matter, it would not mean it was contemporaneous with the building
Third, the workshops and tombs of the workers totaled about four thousand people. Where are the 200,000?
Fourth, there is no evidence connecting the pharoah Khufu with that building, or that there even was such a person. The meaning of the glyphs found in the "relieving chamber" is vague in the extreme. Read William Fix, "Pyramid Odyssey"