No. No aliens/reptiles built the pyrmids.
There's not just 3 pyramids in the desert, you know. The pyramids are surrounded by a city (and it's just across the river from Cairo.) The city
has all sorts of things in it, including the tombs of the Egyptian workers (people who are described as scribes and sculptors and so forth.)
There's plenty of paintings in the buildings ... no Greys. Just Egyptians. They left behind graffiti, too, with the names of the work crews (and
all sorts of other things.)
Here's the Harvard museum page with a map of the area and some pictures:
And the National Geographic webpage on it: