L.E.
Hi S.!
I have just conquered the potty training dilema for the 2nd time with my 2nd child, and in my opinion your step daughter is not ready. Trust me you can pull out all the stops, but if they are not ready and cooperative, it will never happen. My daughter will be 3 the end of next month, and we just got her trained, and at first it was against her will, but she is very stubborn, and she finally in these last 2 weeks became cooperative.I think also that if you wait til she is ready and more cooperative, it happens a lot faster, with less messes!
Good luck!