Yeah, like i said I've no idea on any of that and I don't think that's information id be allowed to get. Though i know that Bloodborne was made out of good will between Sony and Fromsoft, so I don't think they would put Fromsoft under any contractual obligation, but even of they did, it doesn't necessarily mean that Fromsoft's next game or IP has to be with Sony.
Well, Sony Japan were the producers for Bloodborne, they didn't actually develop Bloodborne. So producer of Bloodborne just refers to someone that made sure the project went smoothly and that Sony did whatever they could to help out.
I don't really have any opinion on it one way or another. But looking at it from a Fromsoft perspective, if this is the next evolution in Fromsoft ARPGs and even possibly the start of a new series, you'd want it to reach as many people as possible.