Do you ever ask yourself why God would need, in this case, Ahab, who he "made" to sin, to convince a person to sin? If he already had the mighty power to make Ahab do any evil, of what necessity would he then need to persuade him of anything? How is Ahab's own mind and decision making process of any consequence?
For one, this is the word of a prophet saying that a spirit, of its own accord, would direct prophets to tell Ahab that he would prevail in battle. God is here allowing that spirit to operate in order to persuade Ahab. Are any of the words coming from God?
Does God allow us to be tempted? Sure. But we don't have to BE persuaded.
Jehosaphat did not consider those lying prophets to be from the Lord.
So they said, “Go up, for the Lord will deliver it into the hand of the king.”
7 And Jehoshaphat said, “Is there not still a prophet of the Lord here, that we may inquire of Him?”
So the king of Israel said to Jehoshaphat, “There is still one man, Micaiah the son of Imlah, by whom we may inquire of the Lord; but I hate him, because he does not prophesy good concerning me, but evil.”
And Jehoshaphat said, “Let not the king say such things!”
So the one prophet who was actually speaking God's words is about to come.
13 Then the messenger who had gone to call Micaiah spoke to him, saying, “Now listen, the words of the prophets with one accord encourage the king. Please, let your word be like the word of one of them, and speak encouragement.”
14 And Micaiah said, “As the Lord lives, whatever the Lord says to me, that I will speak.”
Thus we see that it wasn't God speaking through those prophets at all. God didn't lie.
And after the true prophet of God reveals that they are NOT speaking God's words, the prophets are greatly offended.
24 Now Zedekiah the son of Chenaanah went near and struck Micaiah on the cheek, and said, “Which way did the spirit from the Lord go from me to speak to you?”
25 And Micaiah said, “Indeed, you shall see on that day when you go into an inner chamber to hide!”
Ahab was already convinced that the one true prophet who spoke God's words would keep him from going to war. Now if God had put that decision in his mind for him, there's no reason to lie to him to convince him that he should be disobedient to His words. Micaiah did prophecy the truth. In fact, though it's not said, it's clear that his first words, to tell Ahab to go into battle and that he would prevail were dripping with sarcasm. Ahab recognized that sarcasm as we can see from his response.
And he answered him, “Go and prosper, for the Lord will deliver it into the hand of the king!”
16 So the king said to him, “How many times shall I make you swear that you tell me nothing but the truth in the name of the Lord?”
Micaiah's sarcasm causes Ahab to understand that God hadn't at all been speaking through those other prophets.
So Ahab knew that the true prophecy of God was that he would be killed in battle that day. But in spite of that he went anyway. What we are shown is that Ahab already had a hard heart against God's word. That was his decision, not God's. In his patience, God gave Ahab every opportunity to see the truth and save his own life. Of what necessity would this have been if God was already directing Ahab's feet?
The purpose of the event was to give Ahab the truth so he could make an informed decision. Ahab rejected that truth.
The spirit that was a lying spirit probably was Satan or one of Satan's own angels. Satan often went before God to gloat and God allowed Satan to tempt Job. This in no way supports God's predestined direction of men. In fact, you yourself have allowed that people in the OT had free will and that the OT demands that. It does of course. Though your concession should lead you to understand that never changed and there's no scripture saying it did.
Besides, in the long run you've got this problem. If God makes some people to sin and some people to obey - predestines them, Paul has said that it's everyone, not just some. "For all have sinned and fallen short of the glory of God."
That would mean that we're all caused by God to sin. That makes no sense from my reading of the scripture.
