I know she lived there for two years, and I assume that means that address was on all her stuff. I thought that if the police had probable cause to believe a missing person was inside a place, they can go in.
The Sheriff of Polk county already said he would have taken Brian in based on the van being there, so that seems like the police then did indeed have probable cause. I can't get over how they can take the van, but they can't go in and see if Gabby is in the house. I don't mean search it, but check for her -- the subject of the missing person's report.
I know they claim she got missing in WY, but who knew that? Just because that's where the last phone call came from? But Brian was there, too, at the time, and then he was clearly in FL next. So why couldn't Gabby be, too?
For all anyone knew at the time, BL could have kicked Gabby out of the van in another state. What they did know was her van, the last thing she'd been in, was at her own residence. That's why I think the police just botched everything from start to finish.