Why Pharaoh did not kill Moses?

Pharaoh considered themselves as gods- Sun god. They received worship from people. Pharaoh was not a public servant, instead all public were his servants. There are many who think Moses confrontation with Egypt was an imaginary story. The reason they state is that Pharaoh could have easily killed Moses and finished off the rebellion. Yes, Pharaoh with his army could have easily arrested Moses and Aaron, and executed them. Moses’ foster mother also would have died as he was eighty years old and if alive should have been over one hundred years.
1) Demonstration of God’s power: Lord prepared Moses to confront Pharaoh. He gave three signs to prove his credentials as the one sent by Jehovah. When Pharaoh asked: Who is the Lord? (Exodus 5:2) Moses demonstrated power of God through three signs: First, staff became serpent showing the God’s power over nature. Second leprous hand demonstrated God’s authority to curse. God is judge of all humanity including all nations. Third, turning Nile water to blood: Demonstration of God’s power over all gods of Egypt.
2) Needed Moses help: Pharaoh needed Moses help to cancel plagues. Pharaoh knew he did not have capacity to stop plagues. Because Aaron’s rod that became serpent swallowed up all serpents that came from Egyptian magicians’ rods. (Exodus 7:12) Pharaoh understood that only Moses could cancel the plagues.
3) Will not concede defeat: In Pharaoh’s worldview by killing Moses, he will allow God of Moses to be victorious. Instead he wanted victory by defeating Moses and His God. By the time he realized the true God, it was too late.
4) Revolt: The number of Israel people were numerous. If they join enemy forces to revolt, Pharaoh could not survive. Moses could instigate a revolt with outside help as he had lived forty years in exile and some other nation may be supporting him.
Nothing or anyone could harm a person when s/he is involved in doing His Will. They enjoy God’s marvellous protection.
Do I have boldness to do His will enjoying His protection?