The exact same thing happened to me, If you discover how to fix it, let me know :)
I had the same issue, but I had to fiddle around inside my save file to fix it.
In my case, I had to open up my save file, scroll down to "data_dialogues_Data," find the last story event listed there, and deleted that off of my file. I made a backup in case something went wrong, loaded up the new file, and used the cheat (~) to manually start up the event, and it worked.
I dunno if this'll work for you guys, but it worked for me. I did end up a few story events back from where I actually was, but everything seemed to play out as it was supposed to. I think I ended up sidestepping the issue by allowing an older story chapter to trigger instead, so this probably isn't an actual fix, so if anyone could find a better solution, that'd be much appreciated.