Because actions have consequences

That is simply not true. Bad people live good lives and good people live bad lives. If God is just, why is this the case? The only way to explain is to come up with an afterlife where the roles are reversed and people are punished disproportionately. An idea borrowed from Egyptians, as jews and christians did not develop this escathology until later.

Regarding the sources, they both claim that it is clear that God hardens Pharaoh's heart, making it harder (not impossible) for the Pharaoh to choose freely. It is the only relevant point brought up by Origen, twice:

But if we believe these writings to be divine and written by the Holy Spirit, I do not think that we should regard the divine Spirit so lowly as to suppose that that distinction was made by chance in so great a work as this, and that at one time God is said "to have hardened Pharao's heart," at another it is said to be hardened not by God, but, as it were, voluntarily. I admit, to be sure, that I am not fit or able in such differences to pry into the secrets of divine wisdom

I see this man as one who understands the difference between, "Pharao's heart was hardened," and, "The Lord hardened Pharao's heart." 

Origen is, as most of these books, tedious and does not say anything relevant as to why God did it. Instead it uses the story as a metaphor for the new testament 🥱. If there is something relevant be sure to tell me, as I only read epistle 4, but there certainly does not seem to be anything else.

Your second source actually disagrees with you: the argument is that God cheats but the pharaoh ultimately had the final decision. That if it wasn't for God's hardening the pharaoh would have done something else.

God’s activity makes Pharaoh’s own obduracy of such a character that he is driven to the point of no return.

God becomes involved in the very sin and rejection of the people. In such situations, the continued divine involvement has the effect of intensifying the sinful behavior of the people, driving it toward its fullest negative consequences as it goes crashing through the gorge.

It also raises a very stupid point in my opinion: he argues that God does not control Moses because Moses rejects his command before eventually accepting it. Now, this might be true for anybody else, but for God this does not work. God wanted moses to do X and Moses does X, whether Moses does not want to is irrelevant. It is insulting, nigh blaspheous, to say an omniscient and omnipotent being has a backup plan.

God is clearly not in absolute control of Moses. For all of God’s powers, Moses is not easily persuaded to take up his calling. In fact, God resorts to a backup plan in providing Aaron to stand with him (see at 4:14). God relates to Moses in such a way that his will is not overpowered.

All in all my conclusion from reading these texts is that Moses and Aaron wanted to let the Israelites go. The Pharaoh did not but was willing to come around. However, God intervened and made it so that the Pharaoh chose not to. Instead of softening he hardens. Instead of healing he kills.