I do not really understand why you would go back hunting instead of staying on the trail.
Once you lose the trail then its time to start doing some grid searches until you find the deer. If the dog was only 15 yards from the deer when it lost the trail it seems like you did not look very hard.
Once you hit a deer it is YOUR responsibility to find that deer, if you have to miss some hunting time because of it thats too bad.

I do not mean to be harsh, I just speak the truth.