A doctor will probably tell you they don't know for sure
I would say no she wouldn't have remembered the conversation, but encephalopathy is only one thing going on. mental confusion , dementia, electrolyte imbalance, it could be a mixture of a million things, episodes may present the same way but be of different combinations of things going on. There are those old manipulations but there is also a progressive illness going on. I think you are making wise steps, very practical and sensible. Maybe one of the nursing homes willnot only meet her medical needs but provide some social stimulation as well. She has made her life require 12 hours of care form someone else. That will increase not decrease. You aren't in a position to give her what is best so there is no need for guilt. The day will come when there will be no doubt, but for now, think of the energy YOU need to get through this and spend your time and energy wisely. You didn't drink her into this situation.