Should I email my fiance's ex to get more information?

My fiance is going to court in about 3 weeks for custody of his daughter. We're working on his case right now and deciding what to include. Basically its cut and dry. My fiance has done nothing wrong according to Ohio's custody laws and the best interests of the child. His ex has kept him away from their daughter purely out of spite. I have several emails between she and myself as well as she and my fiance that show she is only keeping him away out of spite. There are a few things, though, that I want to get her to say. Would it be worth it to email her (politely of course, I haven't said anything rude regardless of her impropriety) about these key facts to illicit the desired information? Or would the fact that I keep in contact with her outweigh the points that we can prove based on what she said? She has said for my fiance and I not to talk to her, but we try to keep in contact 1. Because we think its best for the child to have a peaceful relationship between her parents and step parents and 2. Because we've been encouraged by all our legal aid to keep up contact with her, plus it gives us more padding for our case when she is rude or admits things. I've been leaving her alone, but as I sit here and write some of this I just wish I could get a few more comments from her. What should I do?