That's correct Jeff, based on what I heard. My brother and a couple friends were hiking from Carranza to Bass River to camp that weekend, and he left his car at the Carranza Memorial (with a parking permit). When they returned, there were a bunch of people there with trailered horses, and they told told him what had happened. The police (rangers?) had run my brother's tags to see if he was somehow connected to what went on.
But yeah, the horse people's story matches what's been said here.