Is she OFF feed, or has she never eaten for you? I ask because she may need you to do the "zombie dance" to believe it's alive, not just drop it on the ground. Hold the rat behind the shoulder blades with the tongs, rather than hanging it by the tail, and shuffle it slowly in front of her.
As long as you're monitoring her weight with a scale and she isn't losing, don't worry about going to great lengths to break a fast - she'll eat when she's ready.
Oh, and with the feeding response on some of my girls, there's no way I'd ever be placing a rat in their tubs without tongs. Rat tails just aren't long enough if she misses!