Throwing bodies in a dumpster definitely has a lot of risks, but people still do it and somehow get away with it. It isn't impossible or unfathomable to me that something like that happened-literally, someone got lucky and not necessarily with the work of a perfect criminal mastermind plot. Sometimes, LE just cannot confirm the location of a body. It sucks, but it happens.
If I were to criticize them for something it would be not being more aggressive about the dumpsters and landfills. I definitely agree that that left an unfortunate gap in the investigation. At this moment, I am not feeling like they were wrong to suspect and try to clear the pack of men that surrounded her the entire night, however.