On what basis was Jesus’ death sufficient for redemption according Non-Trinitarians who maintain that Jesus was not eternal God as God the Father is? To Peter Turner’s point A) Scripture is the source that says blood was necessary and that blood was sufficient, question revolves around why a Non-Trinitarian Jesus has sufficient worth to save mankind from sin of He is not God and therefore not infinitely valuable as God is.

“For by a single offering (blood offering) he has perfected for all time those who are being sanctified.”
‭‭Hebrews‬ ‭10:14‬ ‭

.

“he entered once for all into the holy places, not by means of the blood of goats and calves but by means of his own blood, thus securing an eternal redemption.”
‭‭Hebrews‬ ‭9:12‬

To point B) this question is for non Trinitarians, if moderators require a more specific group, to Jehovah Witnesses. (Not for Modalist Non-Trinitarian)
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The OT foreshadowed a coming sacrifice through which sin would be purged and expunged

“For it is impossible for the blood of bulls and goats to take away sins.”
‭‭Hebrews‬ ‭10:4‬ ‭

Animal sacrifices were done in faith anticipating the future redemption of mankind
But why was Jesus’ death/blood sufficient?
If Jesus was merely a coequal to satan or of the same kind any other ‘angel’ as some claim, and NOT God incarnate (as Trinitarians say He is) then why is an angel incarnate a sufficient sacrificial lamb for the sins of mankind?
It is clear that prior to incarnation Jesus existed as a non “Adam” man, two texts, one is His own admission because the conversation was prior to the prepared body

“Consequently, when Christ came into the world, he said, “Sacrifices and offerings you have not desired, but a body have you prepared for me;” “Then I said, ‘Behold, I have come to do your will, O God, as it is written of me in the scroll of the book.’‭‭Hebrews‬ ‭10:5‬,7
“For I have come down from heaven, not to do my own will but the will of him who sent me.”
‭‭John‬ ‭6:38‬

And secondly
“But as for you, Bethlehem Ephrathah, Too little to be among the clans of Judah, From you One will go forth for Me to be ruler in Israel. His goings forth are from long ago, from eternity.””
‭‭Micah‬ ‭5:2‬ ‭
If He is not God, as God the Father is God, but a created being on what basis is His sacrifice sufficient?

“But when Christ appeared as a high priest of the good things that have come, then through the greater and more perfect tent ( not made with hands, that is, not of this creation) he entered once for all into the holy places, not by means of the blood of goats and calves but by means of his own blood, thus securing an eternal redemption. For if the blood of goats and bulls, and the sprinkling of defiled persons with the ashes of a heifer, sanctify for the purification of the flesh, how much more will the blood of Christ, who through the eternal Spirit offered himself without blemish to God, purify our conscience from dead works to serve the living God.”
‭‭Hebrews‬ ‭9:11-14‬

Why is His blood sufficient if he is not the eternal God?
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Animals were used in substitution for sin as foreshadowing
One man could die for another man or take the punishment in substitution
Since when can an angel substitute the sins of all mankind?
It would make sense if it were the eternal everlasting God but a created being makes no sense, humans are created, as are angels why is one angel worth all of mankind?
This is from the perspective of Jehovah's Witnesses. A full explanation of Jesus' ransom sacrifice can be found in chapter 5 of the book, "What Can the Bible Teach Us?"

Jesus' death is sufficient for redemption from sin on the basis that Jesus was a perfect man, without sin, just as Adam had been.

When Adam was created, he was perfect, but when he disobeyed God, he became sinful, selling himself and all his children to sin and death. (Romans 5:12; 7:14) In order for Jehovah God to have a legal basis to repurchase mankind, forgive sins, and restore humans to a perfect state with the opportunity to live forever, there must be a corresponding ransom to replace the life that Adam lost, one who lives their whole life without sin, obedient to God. (1 Tim. 2:6; Romans 5:19; 1 Cor. 15:21, 22) No descendent of Adam can serve as this ransom because we are all born sinful, imperfect. (Psalm 49:7, 8)

To provide the ransom, Jehovah miraculously caused one of his perfect spirit sons to come to earth as a human. (1 John 4:9; Luke 1:35) This was Jesus. Jesus remained obedient to God until death. Later, when Jesus returned to his Father in heaven, he presented the value of his perfect human life to Jehovah as the ransom. (Hebrews 9:24) Furthermore, Jesus disproved Satan's accusation that no human would remain obedient to God if that person was severely tested. (Job 1:9-11; Prov. 27:11)