Much more able scholars than I have debated the role of the Sovereignty of God in the free will of mankind (not just the Virgin Mary) so I will leave it say only that God knew Mary would assent because He is Eternal and is not bound to any of our concepts in time but that Mary herself did not have the foreknowledge that she would say yes. So her act of assent was freely given since it was not a forced consent and because she made it in obedience to God’s command. Not because she believed it would fullfill the grace God had bestowed on her in her immaculate conception.
I hope we can agree that the Virgin was a humble servant of God whom she declared her Savior.
Which is her admission that she HAD sinned. If she was born without the stain of original sin, and led a perfect sinless life, then she would not have needed a savior.
If that were the case, then when she called God her *savior* she would have been lying, which would have been a sin.
So then she wasn't sinless.
She was a decent enough young Jewish woman whom God used to incarnate His Son. She was not a demi-god, nor incorrupt, or immaculately conceived. She was not the object of anyone's worship or adoration. She was a sinner saved by grace whom God used to His end.
If Rome would not force upon us things regarding Mary that cannot be deduced from Scripture, agreement would not be that difficult.
Actually Mary was never asked..the angel told her what was to come and even named the child ...