from my experience, the biggest trick to get them not smells your scent is wash the antlers off (it gets em good and stinky) and wear a set of laytex/rubber gloves. that way they can't smell your scent, and the majority of the dog slobber is off. also be sure to throw them, and now walk and plant them, otherwise they will follow your trail to the antler.
I've also found that getting extremly over excited every time along with the treat helps. My dogs go nuts when I get super excited and continously shout "find the bone" and "good boy" when they do. I fall to the ground and roll around with them.
Also get her out as much as possible, the more "wild" ones she can find, the better she will get at it. I've also learned that my dogs smell old horns WAY better than fresh horns. I've seen them trip over a fresh antler, but wind an old one from a ways away....
But as you said, just keep practicing, and she will get it!!!
