The Egyptians didn’t think Moses was actually Yahweh / God. Neither did the Israelites. That would be absurd.
Theologians who say that Jesus is actually God don’t say that Jesus is Yahweh in the same way that Moses was.
Did God fail to do what He said He was going to do?
So the LORD said to Moses, “See, I have made you like God to Pharaoh, and your brother Aaron will be your prophet.