First, allow me to say that I do not claim to be a theologian. And again I do not ask you to believe as I do.
Having stated that, yes, you are correct in that my beliefs are unorthodox. , maybe I am in the new vanguard of Nuevo Christian or something equally unsure. I believe what I believe, and respect the beliefs of others without the age old condemnations of those who believe differently.
The truth is, belief in God can only truly be known subjectively in each one of us. That could be unconventional as well.
To answer your questions as best I can, yes, holy errors, batman.

I don't see how that is not a possibility, and most probably a very good probability.
Next, IMHO, no one should trust it's content, especially in light of it's history. What should be done is examine it critically using the tools we have at hand and arrive at your own conclusion based on that, as well as other tools, meditation, intensive study, scientific methodology, and your conscience. That should suffice.
By that time, you are better able a make an educated guess, than just dismissing something outright without at the very least going on someone else's word for it.
What I used was not just the Catholic, but also the King James Version, as well as what I've learned from some of the most recent discoveries such as the Dead Sea Scrolls. And I did not stop there. I used the Torah, the Kabala, texts from the Tanakh, the Koran, the Vedas and Bhagvad Gita, as well as teachings from Buddha, Celtic Druids, Wiccan, agnosticism, and anything I could find from early American Indians, and Australian Aborigines, etc., basically whatever I could get my hands on, and modern metaphysical writings.
I've already explained how and why things happen that are not Gods' Will. Remember free will? Remember being in His image and thus Creating our own realities, however imperfectly? IMHO He, by the very act of giving us free will, allows us to do this.
And what's more, free will cancels out Destiny. Does this stance, I your opinion, mean I am soft on the issue? I don't think so.
I believe Gods' words are contained in the bible because of all the methods I have used, scientific method, cross tabulation with other books, meditation, experiences in life, and my own conscience have shown me they are.
I cannot give you better answer than that because IMHO it isn't possible due to the subjective, rather than objective, nature of it. You seem to want concrete proof, and no one on this planet can give you that, except yourself.