Salvation is not through any of the prophets. That is not the point.
I have NEVER heard ANYONE say that the writings of EGW were above the Bible. It is not productive to pit one against the other.
As for me, the bible is the only source of spirit of prophecy.Daniel and John was commission by God to reveal the future coming events of this world. Any prophets that comes after them should be tested whether the words they spoke was from God or not,by all christian believers in order not to be deceived, Bible warns us from old testament to the new testament" beware of false prophets" that includes E. White. Many adventist says that E.White did not claim to be a prophet while believing on her spirit of prophesy. If she claimed to be a prophet, did she passed the criteria of being a messenger of God? I don't think so, because she wrote that" all religions outside adventist are babylon and probation are close for them", so Great disappointment of adventist Oct.22, 1844 is the test. Although W.Miller is the author of second coming of Jesus, she strongly endorse it by saying" she saw in her vision,that the chart made by W. Miller was directed by the hand of the Lord and should not be altered". If that is so, why then it failed, it is because W. Miller revelation is not from God and E. White endorsement is a big mistake,her vision is not from God.
A big amen to you my brother! If you want you can view or join the discussion on Fidelis' thread where I have focused on the 1844 test. God be with you my brother.