any download from amazon should have device specific DRM, so if you downloaded it for the PW2, it should be unreadable in Kindle for PC, and should not automatically appear there - is it ?
I assume transfer via USB asks you what device is is going to and that the PW2 is registered ?
this is amazon help for that process. is this what you are doing ?
https://www.amazon.co.uk/gp/help/cus...deId=201733700
? why not download it direct from amazon to PW2, via wifi ?
the other , much simpler way that i would use is to ask amazon to send it to your Kindle for PC install , registered to the same amazon account,( using version 1.7 or older) , then add it to calibre ( with tools installed) and you have a version that now works anywhere.... sideload that..