I was very interested to read your post, but sad as well. My Mum, (sadly no longer with us), experienced similar delusions, but was never diagnosed with Lewy Bodies. She was admitted to the mental wing of a hospital, where she deteriorated daily and eventually died of a heart attack. The consultant kept changing her meds.,but she just got worse. The mental unit was awful and she was amongst drug addicts and suicidal people of all ages. She was neglected and became so thin and frail. It broke my Dad's heart.
Like your Mum, she thought she was in a hotel and said that at night she was being raped. She was also very anxious whenever we took her for a drive in the car and said we were being watched by the nurses, who had secret cameras everywhere.
It was very distressing for all of us, to see her in such a state and we didn't know how to talk to her. I think you do have to go with her flow, but try to distract her by asking her to recall happy events that happened in the past.
To this day, we have not been given a diagnosis of my Mum's condition. It was like pulling teeth, trying to get any information from the staff at the hospital. If she did have Lewy Bodies, then that might explain my Parkinson's
I do hope you get better treatment for YOUR Mum. You have to nag the medical profession and don't be fobbed off......keep asking them questions. I wish we had.