Complete and total BS.
Yes,there were dog teams,but there sure as hell wasn't anything secret about them. They walked point in large conventional units because they could smell out ambushes,and sometimes even smell out booby traps.
Dogs were also sometimes used in WW-2 for the same purposes. When you are fighting in the jungles and can only see a few feet in front of you,dogs that can smell out the enemy can save a lot of lives.