I have been in similer situations, I often walk Happy off leash, but she also hase extremly reliable obedience commands, and she does not leave my side, a while ago an off leash golden comes running up when he saw Happy, Happy remained in a heel with me, I wias in a panic and yelled to the kids that Happy does NOT always get along with other dogs, they just half heartidly call the dog in between laughs, obviously the dog did not listen, thankfully Happy did not mind the dog, I was with a whole group so we were able to keep someone between Happy and the dog until we could get out of the park. and more recently a big shepherd/chow looking mix comes running up to Happy and Misty when I was walking them on the bike path, Misty was pulling a scooter and Happy was off leash, the dog starts posturing all over my girls, no owners in sight, I am scared out of my mind that the girls wont take to kindly to a large strange dog posturing all over them, so I am on the path kneeling down holding Misty by the collar(she was attached to a scooter remeber) and I already had Happy in a down stay and was petting her and whispering "leave it" and "good girl" to her, waiting for the dog to leave on its own, I could not exactly shoe it away, I had my hands full keeping my dogs from reacting to one incredably rude dog! I am just gald they did not take my fear and get aggressive with that dog, because I was in no way, shape or form at ease, more like frozen in total fear lol