I've called in alot of coyotes with the Circe calls. I believe that Lohman has since bought Circe. They are a closed reed type with a "nipple" that fits between the lips well. Some closed reed types are just round at the tip and are harder for me to get some "emotion" into the sound. One thing I really liked about the Circe, it is extremely loud if I want it to be! I can squeze down my hand at the end of it and blow harder......resulting in a higher pitch. Open the hand a little and blow softer........lower pitch. You might have to put a little more "flex" in the reed to get some calls to do this, but it works great for a closed reed sound. Alot of rasp in it too.
I don't believe that coyotes think of it as a rabbit, I believe that they sense the agony and emotion of a prey animal getting tore in two while still alive. Coyotes are very afraid of people, but I'd bet money that a recording of a screaming baby/child would work very well to call them in. Just an opinion really, but I bet it would work!
Good luck!