@LTalon they're also carrying around stuff they brought back from the otherside right now, like the rifle that the soldiers gave Sorawo parts for. Sure, the rifle was originally from the regular world but it spent a while over there.It very likely has to do with their increasing "comprehension" of the Otherside and its rules and logic. Not to mention their bodies have literally adapted to the Otherside by now. It was explicitly stated that once you go to the Otherside once, it's more likely that you'll go again, but they've gone a lot of times, and are carrying pieces of it inside their bodies--wouldn't shock me that they're more likely to swap sides than the average Otherside traveler.