Apparently some "non-canon" - (which isn't really a valid label if you do research) scripts label this realm a prision, satan was sent here first. The garden was on a slightly different plane, when adam and eve were tricked their natures placed them in this realm under satans authority, requiring them to be redeemed from Satan.
Witnesses believe a lot of stuff that screws up their ability to answer other questions. For example because they don't believe in hell, it screws up their ability to explain demons, which aren't angels but spirits of nephlim, because they aren't natural, they don't have a place to go after death, so they just dwell in this plane tormenting people waiting for their judgement.
I've read a lot of other interesting stuff concerning old hebrew text about them, one in particular described one of them claiming that humans err when assuming that they are seeing flying stars. and that its actually the energy they create trying to get into the heavenly realm but exahusting themselves and falling back down to earth as a flame of energy. I think that same text I read mentions when they get close to the heavens they can hear certain decrees like when its time for someone to pass on and the like.