Yes.
Also yes. The Cetainty, the Divinity, and their children are all limbs of the Exegete, and to be considered direct extensions of it. For the Gate needed a successor to finish what he had started. By contrast, the Qurán was a complete revelation and ordained no inheritor.
By proximity.
Yes.
What discrepancies? Who cares. Just be nice to one another, or can you not get along? Reckon without using a Book as an intercessor. Hold nothing against one another. Seperate yourself from those who harm you and leave them unto their own ends. Or defend yourself against those who harm you and become their consequences. Keep your hands and your words to yourself unless you are pressed.
Isn't this where it gets exciting? Reconciliation is an easy thing.