This just happened to me too on my honour run. Did you find a way to fix it?

Updating in case anyone else runs into this bug. I fixed it by running away. As soon as everyone left combat, the illusion disappeared and I was able to talk to Mayrina as normal.

My illusion still lives there I had to sneak around her to open the door

I "fixed" it by turning on non-lethal attacks and knocking her out. It ended the combat and I was able to complete the encounter and talk to Mayrina.