No they don't think otherwise. You just seem to have a hard time understanding the theology of mediation.
Say you fall overboard and the captain sends someone out to save you. Would you refuse their hand, because it was not the captain's hand? Would you push them away, because the captain didn't jump in?
It's either that; or I fail to understand plain English when I read it.
Bonaventure: The gates of heaven will open to all who confide in the protection of Mary. Blessed are they who know thee, O Mother of God, for the knowledge of THEE is the high road to everlasting life, and the publication of thy virtues is the way of ETERNAL SALVATION . Give ear, O ye nations; and all you who desire heaven, serve, honor Mary, and certainly you will find ETERNAL LIFE.
Say you are lost in SIN and GOD sends JESUS to save you. Would you refuse HIS hand, and accept His mother's instead?
God did send someone out and HE is reaching His hand out to you.
If you refuse it until you die, you do die in your sins.
If you accept that hand, you are saved and God does not throw you back in because you failed to meet His criteria for being saved.