I was sold a doll in very poor condition. I decided I was going to make my best attempts at fixing her up since she will just stay in my collection anyhow. (I have no idea how someone can destroy a doll this way ) But anyhow....She is the squishy silicone vinyl and some of her fingers are torn apart. I thought I could use Sili-Poxy but it didn't work at all.
Does anyone know what would work best to glue them back together?

You are brave! I wouldn't have even accepted a doll like that. I'm just a collector so I'm not help in this matter but I hope you can find someone to help you. Maybe a Youtube search? Or reach out to a silicone artist. Best of luck to you.