So sorry to hear of all of your problems and cannot imagine what you are going through. I truly hope that all works out the best for you so that you can get to enjoying the lifestyle of camping you have been longing for while working through these frustrations. As an owner of a QBOK I hope to never experience them.
I am by nature a curious person and am wondering if there is anything in common with your unit and others that may have problems similar to yours (besides the obvious brand and model) requiring a trip back to the factory. My head goes right to build date (timeframe), purchased off a lot vs. custom ordered, etc.
Jack of all trades - Master of none
2012 F350 CC DRW - 6.7L PSD
2014 Sabre 36QBOK