I’m not saying they’d have got free if left unguarded, tho maybe they would. I’m saying - if DW stages a home invasion and then at some point leaves the home with no co-conspirator left behind - at that point he no longer has control of the hostages. MOO He has no idea what steps they might take after he’s gone, who else might come along, anything. Plus it’s their own home, they know where everything is and how it works.
After surrendering control of his hostages in their own home, IMO he’d have to be an extreme idiot to return to the crime scene later in the day. But of course he is an extreme idiot - when he went on the run, he updated FB to reflect his new location. Being such an idiot, maybe DW would leave & then return to the scene of his crime.
But he’d have to realize, at least on approaching, that he has no way of knowing what he’s about to walk into. IMO description of him re-entering the house from the Aussies didn’t sound like someone walking into a totally unknown scene with huge potential for peril - no scoping it out or listening for movement.
IMO it sounded like he re-entered with confidence, like he felt secure about what he was heading into. That IMO seems to point to there being someone in there he trusted to maintain control.
All JMO and maybe totally wrong! Who knows! no one but DW (and any co-conspirators). Maybe he really is such an idiot that he didn’t realize the risk he was taking. If so, it’s just too bad he didn’t suffer the consequences.