I only have one boa so not a whole lot of experience here. However from what I've heard Boas can be very food-driven snakes and they feed very well for the most part. No it will not harm her at all, f/t prey is the recommended choice of food for snakes. If a ball python can switch to f/t prey from live, I have confidence that your boa will too. I would first try to wiggle the prey item in front of your snake and if she doesnt budge, then leave it in there overnight (saving time right there b/c you couldn't do that with live rats/mice)and see what went down the next morning. Hope this helped, someone with more experience may add on to this.