Imshael Glitches

I experience the exact same random glitches. Barrier appears if you hesitate before running through the first "doorway" to face Imshael. Sometimes the spiders and demons attack with Demon-form Ishmael, other times they wander around aimlessly and can't be targeted. Imshael might or might not be visible in human form the entire time, but there is always a diamond where he starts out. I kill his first demon form and then nothing, all the barriers stay up, and even using the disengage command my inquisitor stays in aggressor partial combat mode which prevents travel back to camp. I end up quitting to menu, and didn't have the option to load a recent save because my 2 auto saves were inside the barriers, and my previous save before that was about 4 hours of play earlier. The only difference for me was that in my very first fight with Imshael, I don't remember how, but I ended up underneath the castle floor, in a large dark space with quite a bit of ground to run around on, but bordered by the castle foundations. There was no exit except falling off the far edges and dying, so I quit and reloaded where I could. Is there a code or something to punch in and reset the mission? As long as the game has been out, it seems kind of ridiculous there's no way to fix this, but I've looked for hours in the forums, and see nothing...
Almost forgot, I'm playing on the XBox One.