The meaning of the Hebrew Qayin is "spear." I don't see how that relates to being the promised Redeemer.
I think we can do better than to assume that somehow Job's knowledge of God came by way of handed-down religion from Seth. Or Cain.
Who makes the Bear, Orion and the Pleiades, And the chambers of the south -- Job 9
Can you bind the chains of the Pleiades, Or loose the cords of Orion? Can you lead forth a constellation in its season, And guide the Bear with her satellites? -- Job 38
Behold now behemoth, which I made with thee; he eateth grass as an ox. -- Job 40
Though the river rages, Behemoth is unafraid; he remains confident, even if the Jordan surges up to his mouth.-- Job 40
Can you catch Leviathan with a fishhook or tie his tongue down with a rope? -- Job 41
We have this set of exchanges between God and Job that is of any other interchange between God and any other man, in which God validates Himself through His creation rather than divine revelation or reference to His promises to ancestors or His acts in favor of a group of people. With Job, uniquely, God focuses on His creation.
The heavens are telling of the glory of God;
And their expanse is declaring the work of His hands.
Day to day pours forth speech,
And night to night reveals knowledge.
There is no speech, nor are there words;
Their voice is not heard. -- Psalm 19
That which is known about God is evident within them; for God made it evident to them.
For since the creation of the world His invisible attributes, His eternal power and divine nature, have been clearly seen, being understood through what has been made, so that they are without excuse.
For even though they knew God, they did not honor Him as God or give thanks, but they became futile in their speculations, and their foolish heart was darkened. -- Romans 1
I think that Job knew God through creation, because clearly from Psalm 19 and Romans 1, God has made creation sufficient to know His existence and character. Creation is such a sufficient witness of God that creation alone is sufficient for God to judge men by, so that because of the witness of creation--even only creation--man has no excuse not to acknowledge God.
God did this so that they would seek Him and perhaps reach out for Him and find him, though He is not far from any one of us. --Acts 17
So...what if by the witness of creation alone--which is sufficient for belief as we see in Romans 1 and that being God's intention as we see in Acts 17--what if a man does acknowledge God through creation? I think Job is an example of such a man.