Hey PootyyhePirate, thanks for your report. We'll try to reproduce the issue here but it sounds like it's going to be a challenge, on your side you could try to repair the session. On the sessions screen select the session you and your friends where playing and press LT. This opens the settings for that session, in there you can press X to repair the session. If that works than at worst you'll have to restart the combat but you should be able to continue the game.