I've been having this issue for a while now, and decided to stop playing it because of this bug. When I finally killed Jacob Seed, nothing out of the ordinary happened. When I checked the map his figure didn't show he was dead. I uninstalled, restarted, all sorts of stuff but couldn't fix it. I couldn't even go and kill Joseph.
Sorry if I didn't put a lot of information, been a while since I even got on.

