LE doesn’t work that way here. If you remember the case of Aniah Blanchard, they released a video of just her, even though they also had footage of the suspect around the same time. They intentionally left him out. They knew before they released that video that this was their guy. I can’t speculate as to why it was released that way except that they were setting bait. Possibly hoping that if she were still alive, he would release her once he saw that. Because if I’m not mistaken, he had priors on kidnapping.
The video in this case is much different. We see the entire camera range from the moment she entered the shoulder until LE arrived. They didn’t withhold anything, at least not at this point. But they also offered nothing to go with it. That doesn’t mean they don’t have something prior to this or after this that they are laying groundwork on.