I'm not smart enough to figure this out on my own...But your post left me with a couple of questions...
Realizing from God's Word that Jesus' body and blood must have been holy, sinless, and incorruptible, the material cannot any of it have come from a descendant of Adam, who was made of the first sinless batch (Genesis 1:26-27,31; 2:7), and the only one who had all the components from which Elohim made the first soul by breathing life into the DNA to make a him-with-a-Y-chromosome.
As we know the bible says that life is in the blood...I don't know if Adam was created with any blood (I assume not) in his system but it appears to me that after Adam 'ate of the fruit' his body became dependent on blood...Bad blood...
But if through the artifice dogma of her immaculate conception in her mother's womb (name of mother?) was so, would that not then commensurately imply that, having a sinless bodily constitution, thus incorruptible, and its function not interrupted by crass human stoppage of the flow of life-giving blood throughout it, could she therefore logically die? Answer: No.
Since life is in the blood it would seem as well that sickness, disease and death are also in the blood...
You mention that if Mary had a sinless bodily constitution (Catholic fantasy) that she couldn't die...I would assume that she couldn't age either...Yet, Jesus having a sinless bodily constitution did die...
Which brings me to the question, if Jesus aged and died, how is it that his body was holy and incorruptible and as God why would he even need blood??? And, if Jesus' body was holy how could he have had the human emotions such as temptation???
If Jesus wasn't fully human why did he even need a mother???
So far, I'm convinced from scripture that God put Jesus' body in Mary's womb and was pretty convinced Jesus had a body just like mine...
So we might ask 'When did the Holy Spirit impart the God seed to the soul of Jesus via His spirit? We cannot answer that. But we can ponder it! Since the behavior mechanism of the human is the soul, and since the soul is connected to the body via the brain (and that is not finished development until about age three), and since the spirit is connected to one via the soul connection, at what stage in development of the soul does the spirit be connected?
We may presume the spirit is with the soul at some time int he womb, but this does not require that Mary be sinless! Since the life is in the blood, and the Mary blood adds n chromosomes or DNA to the blood of the growing person in her womb, she is not imparting her life, her blood to Jesus. The Maridolatry is based upon nothing more than assertion by men who had no clue to the embryology of gestation!