I wonder if the change in placement of the phrase divider (comma or colon, depending on Bible version) from Isaiah to Luke was purposeful by the Evangelist, or just an accident? Since the Holy Spirit is involved, you'd have to say it was a "happy accident" a la Bob Ross. It changes the meaning of the text, but both are true and provide platforms for meaningful reflection.
Isaiah ch. 40:
3: A voice cries: "In the wilderness prepare the way of the LORD, make straight in the desert a highway for our God.
This is telling us that the way needs to be prepared IN the wilderness. John of the Cross expanded on that concept quite a bit!
Luke, ch. 3
4: As it is written in the book of the words of Isaiah the prophet, "The voice of one crying in the wilderness: Prepare the way of the Lord, make his paths straight.
Luke is alluding to John the Baptist, as well foretelling all the voices in Church history calling people out of the world and back to Christ.
This certainly includes Mary, circa Revelation ch. 12
5: she brought forth a male child, one who is to rule all the nations with a rod of iron, but her child was caught up to God and to his throne,
6: and the woman fled into the wilderness, where she has a place prepared by God, in which to be nourished for one thousand two hundred and sixty days.