Imshael Glitches

I have tried to complete the "Call me Imshael" quest a couple times now. Each time I'm met with a different glitch. First after finishing the last battle with  Red  Templars and demons the "Barred" door would not open, and I had the red dot in the floor glitch, which i've already read about here.

So I went back and restarted the quest over again even though it meant wasting an hour or more of game play. This time the "red dot in the floor/ barred door" glitch did not occur. So I enter the area to fight Imshael. After several times of losing badly, I decided to come back and fight Imshael when I and my team are stronger.

So several hours of game play later I return to fight Imshael. Now as I move toward the already opened doorway to fight Imshael, a magic barrier pops up and I can't enter until I go back to the top of the stairs where the supply crate is, then the magic barrier disappears and i'm able to enter, however now when I enter there are 2 Imshaels, one in human form and one in the Imshael spider demon form. Human Imshael just stands here and says nothing, but the spider demon attacks. There are also red templars in the room but they do not attack. Upon defeating the Spider Demon Imshael, the human Imshael tells me about my choices, after telling him i going to kill him, he disappears and the red templars attack along with giant spiders. After defeating all enemies the magic barrier blocking my way upstairs remains and I cannot proceed. The map still shows a diamond where the Human Imshael was and indicates that I still need to kill Imshael although there are no more enemies in the area. 

I there any work around for this?

I already downloaded and installed the lastest game update.

I would lose about 4 or 5 hours of game play if I went back and started the quest again.

Thank you, Jheels5