If you have a friend who could hold the dog on a leash, you could, if you feel safe, walk her past him with you between her and the dog. That way if she spooks, it should be away from him AND away from you. Don't put her between you and the dog or she might spook away from him and right on top of you.
Give her lots, LOTS of room--in other words you & she to be quite a distance from the dog the first time you walk past him. You be matter of fact, ho-hum--what dog? no big deal, keeping your focus forward to the point you are walking to.
If she handles that calmly, then rinse and repeat , but a bit closer. If she seems nervous or upset, then increase the distance untill she can relax as you walk past. After however many passes it takes (she is the one who decides), you and she will finally get close enough for her to be calm and even curious close to the dog. When she shows calm curiosity, she has probably conquered her fear of the horse-eating dog.
Just wanted to throw out another option,,if you have the time and a helper.