I was in the US Navy Nuclear Power Program for nine years, and I worked in the Nuclear Power Generating Industry for sixteen years. I am prepared to believe this story on face value. I have no independent knowledge of the incident, though I could look it up if I had a mind to do so. But I will say that it could have happened, in just the fashion described in the news article.
First of all, the camera did not shutdown the reactor, the plant operators did. What the camera did was interfere with a control panel. What I infer (from what little the news article has to say) is that a signal emanating from the camera caused the pump controller to (incorrectly) sense that the water level was too high. The controller would then slow down the pump?s water output. This, in turn, would result in a low water level, and it might happen very quickly. Look at this from the point of view of the operator. All they saw was a sudden, and unexplained, loss of water level. Their training would have required them to immediately shut down the reactor, as a precautionary measure (i.e., in an effort to prevent the situation from getting worse). Putting the plant in a safe condition, until such time as the cause of the situation can be determined and corrected, would have been their highest priority.