Oddly, I feel that interpreting the dogs' sneeze as a “vote” might be overly anthropomorphic. After all, among humans voting “yea” or “nay” on something (often) involves multiple deliberative processes and performing acts intended to bring about a desired outcome. I wonder if the dogs' sneeze might be interpreted as a physiological response in anticipation of a hunt or "collective movement". Of course, there isn't a big difference in those interpretations.
BTW, I've never noticed any of the many dogs I've owned to sneeze as a signal to another dog or group of dogs.