My sympathies re the sleep situation, it is awful, isn't it?
Re dummies, could you give her a few (identical) dummies for her cot? If she loses one, she might still be able to find another...
Also add cot bumper so dummies do not fall out quite so easily.
This worked for DS1 who was a dummy addict: Undo knot on one "arm", slip dummy ring through, retie knot. DS1 learnt v v quickly how to find his dummy again after I guided his hand a few times. Same idea also currently working for DS3...
Hope some of this helps.
Oh, almost forgot, CC, yes, worked v quickly for DS1 (who was my most demanding baby ): cried when left alone, spat/through dummy out of cot, we went back in in 1,2,3,4 min intervals, he slept after 20min on night1, 10min night 2, and did not cry at all on night 3. He was also about 8 months old at that point.
So good luck with all that.