@odamizu: IIRC at least on Kindle for Android app the situation can be summed up as "books ASIN is not associated with your Amazon account = sync button is disabled".
The app downloads and keeps a catalog of all your books Amazon knows about (= either archived PDOCs or bought EBOKs).
So no use in using retail ASINs / faking ASINs to a value from Kindle Store
As far as sync goes...
I used to use that Wiki "trick" years ago on my Kindle Keyboard ... not sure if it ever worked when I bought my first Paperwhite (PW1) ... the only thing I recall is that Android app sync broke first... and then later I could't even sync between two Paperwhites...