Could that dog be a hog dog who happened to scare up a few deer while on a hog track?
Solo dog??? Not likely a deer dog unless he is young and not wise to run with the pack.
Solo dog not wide open bawlin' on the track??? Not a typical deer dog sort.
But a solo dog who is generally not real noisy could be a hog dog.
I typically use a single curr to hog hunt. Unless me and my bull dog walk under your stand, you won't know we are there or what we are hunting unless the curr dog bays up a pig.